What is a headache

Headache is one of the commonest symptoms experienced by humans. In fact, it is quite unusual not to have at least an occasional headache. Why some people never experience headache is not known. The term ‘headache’ covers any pain around the head, face or neck area. In many cases, you can treat your headaches at home with over-the-counter painkillers and lifestyle changes, such as getting more rest and drinking enough fluids.

It is probably linked with their inheritance of the chemical transmitters that pass messages in the brain from one nerve cell to another. The brain has a control mechanism for pain impulses and the transmitter substances involved in this also play a part in the emotions, As a general rule, happy people have fewer headaches than sad ¹.

Headaches are usually harmless but can create concern about their origin. Very occasionally headaches are a pointer to a serious disease such as brain tumor or stroke. This is why many people seek advice from their doctors and in some cases, are referred to specialist neurologists. Normally the severity of the headache bears no relation to the gravity of the diagnosis ².

A great deal of research has been directed at determining the mechanisms responsible for the production of the pain of headache. While the brain is itself insensitive to pain, its covering membranes and its larger blood vessels are richly supplied by nerve fibers capable of transmitting the experience of pain. Most of the other structures within the head and upper neck, e.g., eyes, ears, nasal sinuses, skin, muscle, joints and arteries are also exquisitively pain sensitive ¹.

This means that disorders in any of these structures may be experienced as a form of headache. The pain is produced through irritation of these structures via mechanical, chemical or inflammatory mechanisms and pain sensitive nerve fibers send a ‘pain’ message back to the brain. The brain can’t always tell where the pain message originated which is why it is sometimes difficult to pinpoint the exact cause of a headache ¹.

Types of Headaches

There are two main types of headache:

1. Primary Headache – which often “just happen” and are not caused by another injury or illness. That is when headache is the disease.
2. Secondary Headache – which are caused by some underlying health condition. That is when pain is a symptom of another disease.

The International Classification of Headache Disorders ³, published by the International Headache Society ⁴, is used to classify more than 150 types of primary and secondary headache disorders.

Table 1. International Classification of Headache Disorder (ICHD)

Part I: the Primary headaches
(1) Migraine—with or without aura
(2) Tension-type headaches
(3) Cluster headache and other Trigeminal Autonomic Cephalalgias
(4) Other primary headaches
Part II: the Secondary headaches
(1) Headache attributed to head and/or neck trauma such as domestic violence, MVA
(2) Headache attributed to cranial or cervical vascular disorder—hypertension, subarachnoid haemorrhage
(3) Headache attributed to nonvascular intracranial disorder—raised intracranial pressure, meningitis
(4) Headache attributed to a substance or its withdrawal—illicit drug use such as cocaine, alcohol or medication overuse headache
(5) Headache attributed to infections
(6) Headache attributed to disorder of homeostasis—hypoglycaemia, hypoxia
(7) Headache or facial pain attributed to disorder of cranium, neck, eyes, ears, nose, sinuses, teeth, mouth or other facial
or cranial structures—trigeminal neuralgia, Bell’s palsy
(8) Headache attributed to psychiatric disorder
Part III: Cranial neuralgias central and primary facial pain and other headaches
(1) Cranial neuralgias and central causes of facial pain
(2) Other headache, cranial neuralgia, central or primary facial pain

[Source ³]

Primary Headaches

Primary headaches are the most common. They include tension headaches, migraine and cluster headaches.

Some primary headaches can be triggered by lifestyle factors, including:

• stress
• eye strain or squinting
• poor posture
• dehydration
• drinking too much alcohol or eating certain foods, such as processed meats that contain nitrates or monosodium glutamate (MSG)
• changes in sleep or lack of sleep
• poor posture
• skipping a meal.

Sometimes there is no obvious cause.

A few headache patterns also are generally considered types of primary headache, but are less common. These headaches have distinct features, such as an unusual duration or pain associated with a certain activity.

Although generally considered primary, each could be a symptom of an underlying disease. They include:

• Chronic daily headaches (for example, chronic migraine, chronic tension-type headache, or hemicranias continua)
• Cough headaches
• Exercise headaches
• Sex headaches

Secondary Headaches

Secondary headaches have a separate cause, such as illness. They include headaches caused by drinking too much alcohol or a head injury or concussion.

Headaches in women may be caused by hormones, and some women notice a link between headaches and their periods. Hormonal changes due to taking the Pill, menopause and pregnancy can also be triggers for headaches.

Some headaches can even occur as a side effect of medication, such as painkillers. People sometimes get headaches when they’re unwell. For example, you may get a headache when you have a cold, sinusitis, flu or an allergic reaction.

There are a lot of illnesses that can cause headaches. See your doctor if you are getting more headaches than usual, they are worse or don’t improve with over the counter medicines, or they are stopping you from working or sleeping.

A secondary headache is a symptom of a disease that can activate the pain-sensitive nerves of the head. Any number of conditions — varying greatly in severity — may cause secondary headaches.

Possible causes of secondary headaches include:

• Acute sinusitis
• Arterial tears (carotid or vertebral dissections)
• Blood clot (venous thrombosis) within the brain — separate from stroke
• Brain aneurysm (a bulge in an artery in your brain)
• Brain AVM (brain arteriovenous malformation) — an abnormal formation of brain blood vessels
• Brain tumor
• Carbon monoxide poisoning
• Chiari malformation (structural problem at the base of your skull)
• Concussion
• Dehydration
• Dental problems
• Ear infection (middle ear)
• Encephalitis (brain inflammation)
• Giant cell arteritis (inflammation of the lining of the arteries)
• Glaucoma (acute angle closure glaucoma)
• Hangovers
• High blood pressure (hypertension)
• Influenza (flu) and other febrile (fever) illnesses
• Intracranial hematoma (blood vessel ruptures with bleeding in or around the brain)
• Medications to treat other disorders
• Meningitis (inflammation of the membranes and fluid surrounding your brain and spinal cord)
• Monosodium glutamate (MSG)
• Overuse of pain medication
• Panic attacks and panic disorder
• Post-concussion syndrome
• Pressure from tight headgear, such as a helmet or goggles
• Pseudotumor cerebri (increased pressure inside the skull), also known as idiopathic intracranial hypertension
• Stroke
• Toxoplasmosis
• Trigeminal neuralgia (as well as other neuralgias, all involving irritation of certain nerves connecting the face and brain)

Some types of secondary headaches include:

• External compression headaches (a result of pressure-causing headgear)
• Ice cream headaches (commonly called brain freeze)
• Rebound headaches (caused by overuse of pain medication)
• Sinus headaches (caused by inflammation and congestion in sinus cavities)
• Spinal headaches (caused by low pressure or volume of cerebrospinal fluid, possibly the result of spontaneous cerebrospinal fluid leak, spinal tap or spinal anesthesia)
• Thunderclap headaches (a group of disorders that involves sudden, severe headaches with multiple causes)

Dehydration

Lack of fluids can cause dehydration and is a common cause of headaches. Fluids are needed for the body to function correctly and may be lost through:

• illness such as vomiting or diarrhea
• vigorous exercise
• excessive sweating
• alcohol
• having large amounts of drinks containing caffeine such as coffee, tea or cola, which cause you to urinate frequently
• working in hot weather or high-temperature environments.

If you are getting a lot of headaches or concerned talk to your doctor.

Tension headache

Tension headaches are the most common type of headache and are what you think of as normal, “everyday” headaches. They feel like a constant ache that affects both sides of the head, as though a tight band is stretched around it. You may also feel the neck muscles tighten and a feeling of pressure behind the eyes.

A tension headache normally won’t be severe enough to prevent you doing everyday activities. They usually last for 30 minutes to several hours, but can last for several days.

The exact cause is unclear, but tension headaches have been linked to things such as stress, poor posture, skipping meals and dehydration.

Tension headaches can usually be treated with ordinary painkillers such as paracetamol and ibuprofen. Lifestyle changes, such as getting regular sleep, reducing stress and staying well hydrated, may also help.

Who gets tension headaches?

Most people are likely to have experienced a tension headache at some point. They can develop at any age, but are more common in teenagers and adults. Women tend to suffer from them more commonly than men.

It’s estimated that about half the adults in the US experience tension-type headaches once or twice a month, and about 1 in 3 get them up to 15 times a month.

About 2 or 3 in every 100 adults experience tension-type headaches more than 15 times a month for at least three months in a row. This is known as having chronic tension-type headaches.

When to seek medical help

There’s usually no need to see your doctor if you only get occasional headaches. However, see your doctor if you get headaches several times a week or your headaches are severe.

Your doctor will ask questions about your headaches, family history, diet and lifestyle to help diagnose the type of headache you have.

You should seek immediate medical advice for headaches that:

• come on suddenly and are unlike anything you’ve had before
• are accompanied by a very stiff neck, fever, nausea, vomiting and confusion
• follow an accident, especially if it involved a blow to your head
• are accompanied by weakness, numbness, slurred speech or confusion

These symptoms suggest there could be a more serious problem, which may require further investigation and emergency treatment.

What causes tension headaches?

The exact cause of tension-type headaches isn’t clear, but certain things have been known to trigger them, including:

• stress and anxiety
• squinting
• poor posture
• tiredness
• dehydration
• missing meals
• lack of physical activity
• bright sunlight
• noise
• certain smells

Tension-type headaches are known as primary headaches, which means they’re not caused by an underlying condition. Other primary headaches include cluster headaches and migraines.

How are tension headaches treated?

Tension-type headaches aren’t life-threatening and are usually relieved by painkillers or lifestyle changes.

Lifestyle changes

Relaxation techniques can often help with stress-related headaches. This may include:

• yoga
• massage
• exercise
• applying a hot flannel to your forehead and neck

Painkillers

Painkillers such as paracetamol or ibuprofen can be used to help relieve pain. Aspirin may also sometimes be recommended.

If you’re taking these medications, you should always follow the instructions on the packet. Pregnant women shouldn’t take ibuprofen during the third trimester, as it could risk harming the baby, and children under 16 shouldn’t be given aspirin.

Medication shouldn’t be taken for more than a few days at a time and medication containing codeine, such as co-codamol, should be avoided unless recommended by a doctor.

Painkiller headaches

Taking painkillers over a long period (usually 10 days or more) may lead to medication-overuse headaches developing. If you take painkillers for your headaches more than twice a week for more than three months, you’ll be at very high risk of getting rebound headaches. Your body can get used to the medication and a headache can develop if you stop taking them.

Painkiller, or rebound, headaches are frequent or daily headaches that develop after taking painkillers for tension headaches or migraines over several months.

A rebound headache develops if you don’t take a painkiller within a day or so of the last dose. You assume it’s just another tension headache or migraine and take a further dose of painkiller.

When the effect of the painkiller wears off, another rebound headache develops and the cycle continues.

Some people even start to take painkillers every day to prevent headaches, which only makes matters worse.

Strangely, painkiller headaches only become a problem for people who take painkillers to treat headaches. They don’t happen to people who take painkillers for long periods for other painful conditions, such as arthritis and back pain.

If your doctor suspects your headache is caused by the persistent use of medication, they may ask you to stop taking it. However, you shouldn’t stop taking your medication without first consulting your doctor.

All the common painkillers available from chemists can cause this problem. They include:

• codeine
• paracetamol
• non-steroidal anti-inflammatory drugs (NSAIDs) – painkillers such as aspirin and ibuprofen
• a group of specific anti-migraine medicines known as triptans, such as sumatriptan

However, some painkillers are more likely to cause medication-overuse headaches than others.

Painkillers containing codeine are most likely to lead to overuse headaches.

To prevent painkiller headaches:

• Don’t take painkillers for headaches on more than two days in each week.
• Don’t take painkillers for headaches for two or more consecutive days.
• Avoid codeine or codeine-containing painkillers such as Syndol and Solpadeine.

Around 70-80% of people with medication-overuse headaches manage to stop regularly taking painkillers and feel much better as a result. The other 20-30% relapse over time and may have to go through withdrawal periods repeatedly.

Treating painkiller headaches

The treatment for medication-overuse headaches is simple – stop taking painkillers.

If you’ve been dependent on painkillers for months rather than years, the best approach is to stop abruptly.

Your headaches will probably get worse immediately after stopping, and you may feel sick or sleep badly, but after 7 to 10 days, when the painkillers are out of your system, you’ll feel better.

• If you’ve been getting painkiller headaches for several years as a result of taking codeine-containing products, it can be dangerous to stop abruptly. Instead, gradually reduce the number of painkillers you take. This is best done under the supervision of a doctor.

Preventing tension headaches

If you experience frequent tension-type headaches, you may wish to keep a diary to try to identify what could be triggering them. It may then be possible to alter your diet or lifestyle to prevent them occurring as often.

Regular exercise and relaxation are also important measures to help reduce stress and tension that may be causing headaches. Maintaining good posture and ensuring you’re well rested and hydrated can also help.

Guidelines from the National Institute for Health and Care Excellence ⁵ states that a course of up to 10 sessions of acupuncture over a 5-8 week period may be beneficial in preventing chronic tension-type headaches ⁶.

In some cases, an antidepressant medication called amitriptyline may be prescribed to help prevent chronic tension-type headaches, although there’s limited evidence of its effectiveness. This medication doesn’t treat a headache instantly, but must be taken daily for several months until the headaches lessen.

Headaches in pregnancy

Headache during pregnancy can be both primary and secondary headache (see definition above under Types of Headaches above). More than 80% of women in the reproductive age group experience headache at some stage making it a common symptom encountered during pregnancy ⁷. Most headaches in pregnancy are benign and may cause a trivial inconvenience to quite significant debilitation.

In most cases of  headache in pregnancy is a primary disorder, including migraine and tension-type headache as the more frequent conditions that affect women asking medical consultation ⁸. Several observational studies have been conducted to evaluate the course of primary headaches during pregnancy. During pregnancy, primary headaches also showed a tendency to change in pattern from migraine without aura to migraine with aura and vice versa or from migraine without aura to tension headache and vice versa: in an Italian study 9% of tension headache patients developed migraine without aura during gestation, while 10% did the opposite ⁹. Up-to-date, tension headache is not correlated with any adverse pregnancy outcomes, even if sample size of the available studies are too small to achieve definitive conclusions ¹⁰.

However, headache in pregnancy may herald the onset of life-threatening conditions such as eclampsia, stroke (hemorrhagic or thrombotic), and Arterio-Venous malformations (AVMs) ¹¹.

Headaches in pregnancy may be classified as follows:

• Benign, for example, migraine, tension-type headache, cluster headaches, analgesic-overuse headaches, and so forth.
• Pathological, from an underlying pathology, for example, a vascular event (hemorrhage or thrombosis) or raised intracranial pressure (ICP) such as in brain tumors and benign intracranial hypertension.

The International Headache Society ⁴ has published a comprehensive classification system for headaches—The International Classification of Headache Disorder ³ (see Table 1 above)

Migraine

Following retrospective and prospective studies dealing with migraine and pregnancy published in the last twenty years show similar results. About one half to three fourths of female migraineurs experience a marked improvement in migraine during pregnancy with a significant reduction in frequency and intensity of their attacks, if not a complete resolution ¹². The remaining attacks show a progressive reduction in the mean pain intensity and duration as pregnancy proceeds ¹³ As a consequence, the 1-year headache prevalence of migraine and non-migrainous headache is lower among nulliparous (woman who has never given birth) pregnant women than in non-pregnant women ¹⁴. Maggioni et al. ¹⁵ reported an absolute improvement during the first trimester, with a further reduction during the second and third ones, a data that has been confirmed by more recent studies ¹⁶, ¹⁷. Differently, the Head-HUNT study found a marked reduction in headache burden only in the third trimester ¹⁴. About 50% of the pluripara (woman who has given birth to more than one child) mothers present a persistent worsening of their headache with following gestations ¹⁵. This is in line with the evidence that multiparous (woman who has given birth to more than one child) subjects more likely experience worsening of headache ¹⁶. Other studies showed no significant differences between primi- and multiparous pregnant women as regards the course of headaches during gestation among migraineurs ¹³, ¹⁴, neither confirming the trend of further improvement after the first trimester. A large Italian study found that the percentage of remissions during pregnancy was significantly higher in the subgroup of patients whose migraine started at menarche and in those suffering from menstrual migraine ¹⁸, even if this last data has not been confirmed by following studies ¹⁷, ¹⁹.

Migraine without aura can start during pregnancy in 1 up to 10% of pregnant women ²⁰, with some retrospective data rising up to 16.7% ¹⁷; this is classically considered a first trimester phenomenon. In other cases, migraine can worsen during pregnancy, especially in the first trimester: this is reported in 8% of cases ²¹. Up-to-date, scientific literature lacks of large and rigorous studies aimed at understanding factors possibly associated with the absence of a clinical improvement during pregnancy ²².

Tension-type headache

Tension-type headache represents 26% of headaches in pregnancy ²³. Tension-type headache would be expected to improve during gestation as female hormones modulate serotonin and endorphins, which are involved in tension-type headache pathophysiology ²⁴. Actually, 17.9% of tension-type headache patients reported no change in the headache burden during pregnancy, with worsening in 5% of cases and improvement in a quarter of women ²⁵. A study found significantly higher remission and improvement rates than in migraine without aura ¹⁵. Whatever if women with tension-type headache showed a great or a modest improvement, this is usually reported as marked as for the migraineurs ²⁶. On the contrary, tension-type headache rarely worsens during gestation [16] and, according to some Authors, it never does ¹⁵.

Cluster headache

Cluster headache is a relatively rare primary headache, severe in intensity, stabbing in quality, highly debilitating, associated with autonomic symptoms and affecting men more frequently than women. Scientific literature lacks of large prospective studies about the effect of pregnancy on cluster headache, as it is seen in less than 0.3% of pregnancies ²³. Despite the rare cases in which the first attacks occur during the first pregnancy, almost a quarter of pregnant women report that an expected cluster period does not develop during gestation while it may start soon after delivery ²⁷. Otherwise, cluster headache attacks do not change in intensity and frequency in the majority of cases. As a consequence, women who have their first attack before their first gestation usually have fewer children than those who already were mother at the time of clinical onset; this is probably due to the prospective of the treatment limitations in case of cluster headache during pregnancy ²⁷.

Secondary headaches

Pregnancy is a risk factor for a secondary headache disorder. Hypercoagulability, hormonal changes and anesthesia for labor are just some of the multiple factors contributing to the high incidence of secondary headaches during pregnancy.

A recent study by Robbins et al. ²⁸ found 35% of secondary headaches among 140 pregnant women presenting with acute headache: hypertensive disorders of pregnancy covered 51% of these cases (about 18% of total), with preeclampsia as the major cause, followed by reversible posterior leukoencephalopathy syndrome (PRES, eclampsia), reversible cerebral vasoconstriction syndrome and acute arterial hypertension ²⁸. These data place between two previous studies that reported percentages of secondary headaches ranging from 14.3% to 52.6%. In particular, among patients with a primary headache history, longer attack duration is the most common feature suggesting a secondary headache, reaching the statistical significance or just approaching it ²⁹.

The authors ²⁸ show how lack of headache history, elevated blood pressure and abnormalities at neurologic examination are the main red flags for a secondary origin of an acute headache during pregnancy. In the second trimester, a new onset of headache may signal the presence of a pseudotumor cerebri ³⁰, while in case of a severe postural headache a spontaneous intracranial hypotension must be ruled out ³¹. In front of the well-known red flags (see Table 2) brain MRI or CT scan are often required ³². Use of contrast agents such as gadolinium is not recommended, given the lack of data regarding safety to the fetus and its ability to cross the placenta and remain in the amniotic fluid ²³.

Table 2. Red Flags for headache in pregnancy

1.	Headache that peaks in severity in less than five minutes
2.	New headache type versus a worsening of a previous headache
3.	Change in previously stable headache pattern
4.	Headache that changes with posture (e.g. Standing up)
5.	Headache awakening the pregnant
6.	Headache precipitated by physical activity or Valsalva manoeuvre (e.g. Coughing, laughing, straining)
7.	Thrombophilia
8.	Neurological symptoms or signs
9.	Trauma
10.	Fever
11.	Seizures
12.	History of malignancy
13.	History of HIV or active infections
14.	History of pituitary disorders
15.	Elevated blood pressure
16.	Recent travel at risk of infective disease

[Source ³³]

Iodinated contrast should be avoided as well as it may suppress fetal thyroid function ³⁴.

Recently the European Headache Federation ³³ published a consensus statement on technical investigation for primary headache disorders.

Secondary headache features may not differ from those of primary headaches; furthermore, migraine is as an independent risk factor for the development of secondary headaches (e.g., the risk of gestational hypertension increased by 1.42-fold ³⁵, so that recognizing these conditions in pregnant women may be a true diagnostic challenge.

Cerebral venous thrombosis, pre-eclampsia, hemorrhagic or ischemic stroke, subarachnoid haemorrhage (SAH), reversible posterior leukoencephalopathy syndrome, reversible vasoconstriction syndrome, idiopathic intracranial hypertension or pituitary apoplexy must be ruled out as soon as possible (Table 3) ³⁴.

Table 3. Main causes of secondary headache in pregnant women

Secondary headaches during pregnancy
Arterial dissection	Intracranial hypotension
Arteriovenous malformation	Ischemic stroke
Brain tumors	Meningitis/encephalitis
Cerebral venous thrombosis (CVT)	Pituitary adenoma
Choriocarcinoma	Pituitary apoplexy
Cranial neuralgias	Pituitary meningioma
Dehydration	Reversible posterior leukoencephalopathy syndrome (PRES)
Eclampsia and pre-eclampsia	Reversible vasoconstriction syndrome (RCVS)
Head trauma	Sinusitis
Idiopathic intracranial hypertension (IIH)	Subarachnoid haemorrhage (SAH)
Intracranial haemorrhage (ICH)	Vasculitis

[Source ⁸]

Cerebral venous thrombosis

Headache caused bycerebral venous thrombosis has no specific characteristics: it is most often diffuse, progressive and severe, but can be unilateral and sudden (even thunderclap), or mild, and sometimes is migraine-like ³⁶. Headache is present in 80–90% of cases of cerebral venous thrombosis and it is often associated with focal signs (neurological deficits or seizures) and/or signs of intracranial hypertension (nausea and papilledema), subacute encephalopathy or cavernous sinus syndrome, carrying a mortality rate of up to 30%²³.

Pre-eclampsia and eclampsia

Pre-eclampsia occurs in 5% of pregnancies ²³: a progressive bilateral (temporal, frontal, occipital or diffuse) pulsating headache in a woman who is pregnant or in the puerperium (up to 4 weeks postpartum), often aggravated by physical activity, failing to respond to the over-the-counter remedies, may be the herald symptom of this condition, which can associate with visual changes similar to the typical visual aura. It must resolve within a week after blood pressure adjustment ³⁷. According to the International Classification of Headache Disorders ³⁸ headache should have at least two of the following three characteristics: a) bilateral location, b) pulsating quality, and c) aggravated by physical activity.

Ischemic stroke

Headache accompanies ischemic stroke especially within the posterior circulation, in up to one-third of cases and is usually overshadowed by focal signs and/or alterations of consciousness, which in most cases allows easy differentiation from the primary headaches. The risk of ischemic stroke in migraineurs was evaluated using the United States Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality and found to be elevated ³⁵.

Headache has a self-limited course, and is very rarely the presenting or a prominent feature of ischaemic stroke ³⁹. It is usually of moderate intensity, and has no specific characteristics. It can be bilateral or unilateral ipsilateral to the stroke. Rarely, an acute ischaemic stroke can present with an isolated sudden (even thunderclap) headache ⁴⁰.

The diagnosis of headache and its causal link with ischemic stroke is easy because the headache presents both acutely and with neurological signs and because it often remits rapidly.

Subarachnoid haemorrhage

In subarachnoid haemorrhage headache is usually the prominent symptom. The pain is typically severe and sudden, peaking in seconds (thunderclap headache) or minutes, often followed by vomiting and loss of consciousness ⁴¹. Subarachnoid haemorrhage is a serious condition with mortality rate of 40–50% and with 10–20% of patients dying before arriving at hospital. The abrupt onset is the key feature and can help to distinguish from primary headaches with thunderclap features (e.g., associated with exercise or sexual activity). Subarachnoid haemorrhage presents a 20-fold increased risk in the puerperium and it gives a thunderclap headache ²³.

Arterial dissection

Arterial dissection is a rare complication of pregnancy and puerperium. There have been reports of cervical carotid, vertebral and intracranial artery dissection in association with preeclampsia ⁴². Headache is the most frequent inaugural symptom, described as severe, unilateral (ipsilateral to the dissected vessel), with a sudden (even thunderclap) onset. Pain is persistent for days and can remain isolated or be a warning symptom preceding ischaemic infarcts.

Reversible cerebral vasoconstriction syndrome

Headache caused by reversible cerebral vasoconstriction syndrome syndrome is severe and diffuse and typically of the thunderclap type, recurring over 1–2 weeks, often triggered by sexual activity, exertion, Valsalva manoeuvres and/or emotion ⁴³. Headache is often the only symptom of reversible cerebral vasoconstriction syndrome, but the condition can be associated with fluctuating focal neurological deficits and sometimes seizures.

Reversible cerebral vasoconstriction syndrome is commonly associated with the post-partum period, usually within a week after delivery: its severe thunderclap headache usually relapses within a few days, resolving by approximately twelve weeks after clinical onset ⁴⁴. The typical differential diagnosis is cerebral vasculitis, which needs to be ruled out due to the course of the disease and different treatment options.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome is a neuro-radiological clinical entity characterized by insidious onset of headache, impaired consciousness, visual changes or blindness, seizures, nausea, and vomiting, and focal neurological signs. In nearly 2/3 of patients with posterior reversible encephalopathy syndrome, headache is the most common symptom and is usually described as occipital and bilateral and dull in nature ⁴⁵. Symptoms develop without prodrome, and progress over 12–48 h.

Posterior reversible encephalopathy syndrome is often associated with hypertensive encephalopathy, preeclampsia, eclampsia, reversible cerebral vasoconstriction syndrome, renal failure, immunosuppressive therapy or chemotherapy. Posterior reversible encephalopathy syndrome is more common in women and the development of this condition after delivery is unusual. The condition is usually reversible when early diagnosis is established and appropriate treatment is started without delay; symptoms generally resolve within a period of days or weeks while recovery of the MRI abnormalities takes longer ⁴⁶.

Idiopathic intracranial hypertension

Usually during the first trimester, obese women can suffer from a progressive, daily headache, aggravated by Valsalva and position change, associated with papilledema and severe visual deficits, together with tinnitus or sixth-nerve palsies, defining the clinical pattern of idiopathic intracranial hypertension ²³. The headache is frequently described as frontal, retro-orbital, ‘pressure like’ or explosive; migraine-like headache may also occur.

Pituitary apoplexy

Pituitary apoplexy is a rare cause of sudden and severe headache during pregnancy ⁴⁷. The sudden rise of a severe headache, with nausea, vomiting, ophtalmoplegia, altered consciousness and accompanied from onset or later by visual symptoms and/or hypopituitarism must raise the clinical suspicion of a pituitary apoplexy ⁴⁸. The rare clinical syndrome of pituitary apoplexy is an acute, life-threatening condition. It is important to distinguish from the other causes of thunderclap headache ⁴⁹. Most cases occur as the first presentation of rapid enlargement of non-functioning pituitary macroadenomas as a result of haemorrhage and/or infarction.

Treatment of headaches in pregnancy and breastfeeding women

During pregnancy, inadvertent exposure to teratogenic agents can lead to irreversible fetal malformations ⁵⁰. Unfortunately, most patients are not aware of possible teratogenic risks of used medications and their safety profiles during pregnancy ⁵¹.

During pregnancy and breastfeeding the preferred therapeutic strategy should always be a non-pharmacological one. Nevertheless, an undermanaged headache can lead to stress, sleep deprivation, depression and poor nutritional intake which in turn can have negative consequences for mother and baby. Therefore, if non-pharmacological interventions seem inadequate, a well-considered choice should be made concerning the use of medication, taking into account all the benefits and possible risks (Tables 4 and 5). A basic rule should be to aim for the lowest effective dose and the shortest duration of treatment.

Medication is considered safe during breastfeeding if the relative infant dose is <10% ⁵². The risk of adverse events could be minimized by taking medication directly after breastfeeding and discarding all milk for at least 4 h ⁵³.

Table 4. Summarizing table on treatment of headache in pregnant women

[Source ⁸]

Table 5. Summarizing table on treatment of headache in breatsfeeding women

[Source ⁸]

Chronic daily headaches (constant headache)

Most people have headaches from time to time. But if you have a headache more days than not, you may be experiencing chronic daily headaches.

The incessant nature of chronic daily headaches makes them among the most disabling headaches. Aggressive initial treatment and steady, long-term management may reduce pain and lead to fewer headaches.

Symptoms of constant headache (chronic daily headaches)

By definition, chronic daily headaches occur 15 days or more a month, for at least three months. True (primary) chronic daily headaches aren’t caused by another condition.

There are short-lasting and long-lasting chronic daily headaches. Long-lasting last more than four hours. They include:

• Chronic migraine
• Chronic tension-type headache
• New daily persistent headache
• Hemicrania continua

Chronic migraine

This type typically occurs in people with a history of episodic migraines. On eight or more days a month for at least three months, migraines tend to have the following features:

• Affect one side or both sides of your head
• Have a pulsating, throbbing sensation
• Cause moderate to severe pain
• Are aggravated by routine physical activity

And they cause at least one of the following:

• Nausea, vomiting or both
• Sensitivity to light and sound

Chronic tension-type headache

These headaches tend to have the following features:

• Affects both sides of your head
• Cause mild to moderate pain
• Cause pain that feels pressing or tightening, but not pulsating
• Aren’t aggravated by routine physical activity

Some people may have skull tenderness.

New daily persistent headache

These headaches come on suddenly, usually in people without a headache history. They become constant within three days of your first headache. They have at least two of the following characteristics:

• Usually affects both sides of your head
• Cause pain that feels like pressing or tightening, but not pulsating
• Cause mild to moderate pain
• Aren’t aggravated by routine physical activity

Hemicrania continua

These headaches:

• Affect only one side of your head
• Are daily and continuous with no pain-free periods
• Cause moderate pain with spikes of severe pain
• Respond to the prescription pain reliever indomethacin (Indocin)
• May sometimes become severe with development of migraine-like symptoms

In addition, hemicrania continua headaches are associated with at least one of the following:

• Tearing or redness of the eye on the affected side
• Nasal congestion or runny nose
• Drooping eyelid or pupil narrowing
• Sensation of restlessness

Causes of constant headache (chronic daily headaches)

The causes of many chronic daily headaches aren’t well-understood. True (primary) chronic daily headaches don’t have an identifiable underlying cause.

Conditions that may cause non-primary chronic daily headaches include:

• Inflammation or other problems with the blood vessels in and around the brain, including stroke
• Infections, such as meningitis
• Intracranial pressure that’s either too high or too low
• Brain tumor
• Traumatic brain injury

Medication overuse headache

This type of headache usually develops in people who have an episodic headache disorder, usually migraine or tension-type, and take too much pain medication. If you’re taking pain medications — even over-the-counter analgesics — more than two days a week (or nine days a month), you’re at risk of developing rebound headaches.

Risk factors for constant headache (chronic daily headaches)

Factors associated with developing frequent headaches include:

• Female sex
• Anxiety
• Depression
• Sleep disturbances
• Obesity
• Snoring
• Overuse of caffeine
• Overuse of headache medication
• Other chronic pain conditions

Complications of constant headache (chronic daily headaches)

If you have chronic daily headaches, you’re also more likely to have depression, anxiety, sleep disturbances, and other psychological and physical problems.

Prevention of constant headache (chronic daily headaches)

Taking care of yourself might help ease chronic daily headaches.

• Avoid headache triggers. Keeping a headache diary can help you determine what triggers your headaches so that you can avoid the triggers. Include details about every headache, such as when it started, what you were doing at the time and how long it lasted.
• Avoid medication overuse. Taking headache medications, including over-the-counter medications, more than twice a week can increase the severity and frequency of your headaches. Consult your doctor about how to wean yourself off the medication because there can be serious side effects if done improperly.
• Get enough sleep. The average adult needs seven to eight hours of sleep a night. It’s best to go to bed and wake up at regular times, as well.
• Don’t skip meals. Eat healthy meals at about the same times daily. Avoid food or drinks, such as those containing caffeine, that seem to trigger headaches.
• Lose weight if you’re obese.
• Exercise regularly. Regular aerobic physical activity can improve your physical and mental well-being and reduce stress. With your doctor’s OK, choose activities you enjoy — such as walking, swimming or cycling. To avoid injury, start slowly.
• Reduce stress. Stress is a common trigger of chronic headaches. Get organized. Simplify your schedule. Plan ahead. Stay positive. Try stress-reduction techniques, such as yoga, tai chi or meditation.
• Reduce caffeine. While some headache medications include caffeine because it can be beneficial in reducing headache pain, it can also aggravate headaches.
• Try to minimize or eliminate caffeine from your diet.

Diagnosis of constant headache (chronic daily headaches)

Your doctor will likely examine you for signs of illness, infection or neurological problems. He or she will ask about your headache history.

If the cause of your headaches remains uncertain, your doctor may order imaging tests, such as a CT scan or MRI, to look for an underlying medical condition.

Treatment of constant headache (chronic daily headaches)

Treatment for an underlying condition often stops frequent headaches. When no other condition is discerned, treatment focuses on preventing pain.

Prevention strategies vary, depending on the type of headache you have and whether medication overuse is contributing to these headaches. If you’re taking pain relievers more than three days a week, the first step may be to wean yourself off these drugs with your doctor’s guidance.

When you’re ready to begin preventive therapy, your doctor may recommend:

• Antidepressants. Tricyclic antidepressants — such as nortriptyline (Pamelor) — can be used to treat chronic headaches. These medications can also help treat the depression, anxiety and sleep disturbances that often accompany chronic daily headaches. Other antidepressants, such as the selective serotonin reuptake inhibitor (SSRI) fluoxetine (Prozac, Sarafem, others), may help in treating depression and anxiety, but have not been shown to be more effective than placebo for headaches.
• Beta blockers. These drugs, commonly used to treat high blood pressure, are also a mainstay for preventing episodic migraines. Some beta blockers include atenolol (Tenormin), metoprolol (Lopressor, Toprol-XL) and propranolol (Inderal, Innopran XL).
• Anti-seizure medications. Some anti-seizure drugs seem to prevent migraines and may be used to prevent chronic daily headaches, as well. Options include topiramate (Topamax, Qudexy XR, others), divalproex sodium (Depakote) and gabapentin (Neurontin, Gralise).
• Nonsteroidal anti-inflammatory drugs (NSAIDs). Prescription nonsteroidal anti-inflammatory drugs — such as naproxen sodium (Anaprox, Naprelan) — may be helpful, especially if you’re withdrawing from other pain relievers. They may also be used periodically when the headache is more severe.
• Botulinum toxin. OnabotulinumtoxinA (Botox) injections provide relief for some people and may be a viable option for people who don’t tolerate daily medication well.

Unfortunately, some chronic daily headaches remain resistant to all medications.

Alternative medicine

For many people, complementary or alternative therapies offer relief from headache pain. It’s important to be cautious, however. Not all complementary or alternative therapies have been studied as headache treatments, and others need further research.

• Acupuncture. This ancient technique uses hair-thin needles inserted into several areas of your skin at defined points. While the results are mixed, some studies have shown that acupuncture helps reduce the frequency and intensity of chronic headaches.
• Biofeedback. You might be able to control headaches by becoming more aware of and then changing certain bodily responses, such as muscle tension, heart rate and skin temperature.
• Massage. Massage can reduce stress, relieve pain and promote relaxation. Although its value as a headache treatment hasn’t been determined, massage may be particularly helpful if you have tight muscles in the back of your head, neck and shoulders.
• Herbs, vitamins and minerals. Some evidence exists that the herbs feverfew and butterbur may prevent migraines or reduce their severity. A high dose of riboflavin (vitamin B-2) also may reduce migraine headaches.
• Coenzyme Q10 supplements may be helpful in some individuals. And oral magnesium sulfate supplements may reduce the frequency of headaches in some people, although studies don’t all agree. Ask your doctor if these treatments are right for you. Don’t use riboflavin (vitamin B-2), feverfew or butterbur if you’re pregnant.
• Electrical stimulation of the occipital nerve. A small battery-powered electrode is surgically implanted near the occipital nerve, which is at the base of your neck. The electrode sends continuous energy pulses to the nerve to ease pain. This approach is considered investigational.

Before trying complementary or alternative therapy, discuss the risks and benefits with your doctor.

Coping and support

Chronic daily headaches can interfere with your job, your relationships and your quality of life. Here are suggestions to help you cope with the challenges.

• Take control. Commit yourself to living a full, satisfying life. Work with your doctor to develop a treatment plan that works for you. Take good care of yourself. Do things that lift your spirits.
• Seek understanding. Don’t expect friends and loved ones to instinctively know what’s best for you. Ask for what you need, whether it’s time alone or less attention paid to your headaches.
• Check out support groups. You may find it useful to talk to other people who have painful headaches.
• Consider counseling. A counselor or therapist offers support and can help you manage stress. Your therapist can also help you understand the psychological effects of your headache pain. In addition, there’s evidence that cognitive behavioral therapy can reduce headache frequency and severity.

Ice pick headache

Ice-pick headache consists of unilateral, ultrashort (headache attacks lasting seconds) repetitive, transient and localized stabs of pain in the distribution of the first branch of the trigeminal nerve and occurs in the absence of organic disease ⁵⁴. Ice-pick headache, which is also named as “primary stabbing headache” was first defined by Lansche as “ophthalmodynia periodica” ⁵⁵. The exact prevalence is unknown but 2–30% of the adult population is thought to be affected in their lifetime ⁵⁶. Ice-pick headache has a female dominance. The main pathophysiological mechanism underlying ice-pick headache is unknown ⁵⁷. In a case study involving a 39 y.o woman, her pains were completely relieved with Indomethacin 25 mg three times daily for seven days and 6 mg of melatonin per day at bedtime ⁵⁴.

Thunderclap headaches

Thunderclap headaches live up to their name, grabbing your attention like a clap of thunder. The pain of these sudden, severe headaches peaks within 60 seconds and can start fading after an hour. Some thunderclap headaches, however, can last for more than a week.

• Thunderclap headaches are often a warning sign of potentially life-threatening conditions, usually linked to bleeding in and around the brain. That’s why it’s so important to seek emergency medical attention if you experience a thunderclap headache.

Some people may also experience thunderclap headaches as part of a potentially recurring headache disorder, known as primary thunderclap headache. But this diagnosis should only be made after a thorough medical evaluation and elimination of other possible underlying causes.

Symptoms of thunderclap headache

Thunderclap headaches are dramatic. Symptoms include pain that:

• Strikes suddenly and severely — sometimes described as the worst headache ever experienced
• Peaks within 60 seconds
• Lasts anywhere between an hour and 10 days
• Can occur anywhere in the head, and may involve the neck or lower back
• Can be accompanied by nausea, vomiting or loss of consciousness

When to see a doctor

Seek immediate medical attention for any headache that comes on suddenly and severely.

Causes of thunderclap headache

Some thunderclap headaches appear as a result of no obvious physical reason.

In other cases, potentially life-threatening conditions may be responsible, including:

• Bleeding between the brain and membranes covering the brain, often due to an abnormal bulge or ballooning in a blood vessel (aneurysm)
• A rupture of a blood vessel in the brain
• A tear in the lining of an artery (for example, carotid or vertebral artery) that supplies blood to the brain
• Leaking of cerebrospinal fluid, which when present is usually due to a tear of the covering around a nerve root in the spine
• A tumor in the third ventricle of the brain that blocks the flow of cerebrospinal fluid
• Loss of blood supply to or bleeding in the pituitary gland
• A blood clot in the brain
• Severe elevation in blood pressure
• Infection such as meningitis or encephalitis

Diagnosis of thunderclap headache

The following tests are commonly used to determine if any underlying condition is causing thunderclap headaches.

CT scan

Testing for thunderclap headaches often starts with a computerized tomography (CT) scan of the head to search for an underlying cause of the headache. CT scans take X-rays that create slice-like, cross-sectional images of your brain and head.

A computer combines these images to create a full picture of your brain. Sometimes an iodine-based dye is used to augment the picture.

Spinal tap

Sometimes a spinal tap (lumbar puncture) may be needed as well. With this procedure, the doctor removes a small amount of the fluid that surrounds your brain and spinal cord. The cerebrospinal fluid sample can be tested for signs of bleeding or infection.

MRI

In some cases, magnetic resonance imaging (MRI) may be done for further assessment. With this imaging study, a magnetic field and radio waves are used to create cross-sectional images of the structures within your brain.

Magnetic resonance angiography

MRI machines can also be used to map the blood flow inside your brain in a test called a magnetic resonance angiography.

Treatment of thunderclap headache

There’s no single treatment for thunderclap headaches because so many potential causes exist. Treatment is aimed at the underlying cause of the headaches — if one is found.

 

Migraines

Migraines are less common than tension headaches. They’re usually felt as a severe, throbbing pain at the front or side of the head. Some people also have other symptoms, such as nausea, vomiting and increased sensitivity to light or sound.

Migraines tend to be more severe than tension headaches and can stop you carrying out your normal daily activities. They usually last at least a couple of hours, and some people find they need to stay in bed for days at a time.

Most people can treat their migraines successfully with over-the-counter medication. But if they’re severe, you may need stronger medication that’s only available on prescription. This may be able to relieve and prevent your migraines.

There are several types of migraine, including:

• Migraine with aura – where there are specific warning signs just before the migraine begins, such as seeing flashing lights
• Migraine without aura – the most common type, where the migraine occurs without the specific warning signs
• Migraine aura without headache, also known as silent migraine – where an aura or other migraine symptoms are experienced, but a headache doesn’t develop

Some people have migraines frequently, up to several times a week. Other people only have a migraine occasionally. It’s possible for years to pass between migraine attacks.

Symptoms of a migraine

The main symptom of a migraine is usually an intense headache on one side of the head.

The pain is usually a moderate or severe throbbing sensation that gets worse when you move and prevents you from carrying out normal activities.

In some cases, the pain can occur on both sides of your head and may affect your face or neck.

Additional symptoms

Other symptoms commonly associated with a migraine include:

• nausea
• vomiting
• increased sensitivity to light and sound – which is why many people with a migraine want to rest in a quiet, dark room

Some people also occasionally experience other symptoms, including:

• sweating
• poor concentration,
• feeling very hot or very cold
• abdominal (tummy) pain
• diarrhoea

Not everyone with a migraine experiences these additional symptoms and some people may experience them without having a headache.

The symptoms of a migraine usually last between four hours and three days, although you may feel very tired for up to a week afterwards.

Symptoms of aura

About one in three people with migraines have temporary warning symptoms, known as aura, before a migraine. These include:

• visual problems – such as seeing flashing lights, zig-zag patterns or blind spots
• numbness or a tingling sensation like pins and needles– which usually starts in one hand and moves up your arm before affecting your face, lips and tongue
  feeling dizzy or off balance
• difficulty speaking
• loss of consciousness – although this is unusual

Aura symptoms typically develop over the course of about five minutes and last for up to an hour. Some people may experience aura followed by only a mild headache or no headache at all.

Stages of a migraine

Migraines often develop in distinct stages, although not everyone goes through all of these:

1. ‘Prodromal’ (pre-headache) stage –changes in mood, energy levels, behaviour and appetite that can occur several hours or days before an attack
2. Aura – usually visual problems, such as flashes of light or blind spots, which can last for five minutes to an hour
3. Headache stage – usually a pulsating or throbbing pain on one side of the head, often accompanied by nausea, vomiting, and/or extreme sensitivity to bright light and loud sounds, which can last for four to 72 hours
4. Resolution stage – when the headache and other symptoms gradually fade away, although you may feel tired for a few days afterwards

When to seek medical advice

You should see your doctor if you have frequent or severe migraine symptoms that can’t be managed with occasional use of over-the-counter painkillers, such as paracetamol.

However, be careful not to take too many painkillers as this could make it harder to treat headaches over time.

You should also make an appointment to see your doctor if you have frequent migraines (on more than five days a month), even if they can be controlled with medication, as you may benefit from preventative treatment.

You should call your local emergency number for an ambulance immediately if you or someone you’re with experiences:

• paralysis or weakness in one or both arms and/or one side of the face
• slurred or garbled speech
• a sudden agonising headache resulting in a blinding pain unlike anything experienced before
• headache along with a high temperature (fever), stiff neck, mental confusion, seizures, double vision, and a rash

These symptoms may be a sign of a more serious condition, such as a stroke or meningitis, and should be assessed by a doctor as soon as possible.

Migraine diagnosis

There’s no specific test to diagnose migraines. For an accurate diagnosis to be made, your doctor must identify a pattern of recurring headaches along with the associated symptoms.

Migraines can be unpredictable, sometimes occurring without the other symptoms. Obtaining an accurate diagnosis can sometimes take time.

If you have migraines or a family history of migraines, a doctor trained in treating headaches (neurologist) will likely diagnose migraines based on your medical history, symptoms, and a physical and neurological examination.

Your doctor may also recommend more tests to rule out other possible causes for your pain if your condition is unusual, complex or suddenly becomes severe.

• Blood tests. Your doctor may order these to test for blood vessel problems, infections in your spinal cord or brain, and toxins in your system.
• Magnetic resonance imaging (MRI). An MRI uses a powerful magnetic field and radio waves to produce detailed images of the brain and blood vessels. MRI scans help doctors diagnose tumors, strokes, bleeding in the brain, infections, and other brain and nervous system (neurological) conditions.
• Computerized tomography (CT) scan. A CT scan uses a series of X-rays to create detailed cross-sectional images of the brain. This helps doctors diagnose tumors, infections, brain damage, bleeding in the brain and other possible medical problems that may be causing headaches.
• Spinal tap (lumbar puncture). Your doctor may recommend a spinal tap (lumbar puncture) if he or she suspects infections, bleeding in the brain or another underlying condition.

In this procedure, a thin needle is inserted between two vertebrae in the lower back to remove a sample of cerebrospinal fluid for analysis in a lab.

Migraine treatment

There’s currently no cure for migraines, although a number of treatments are available to help ease the symptoms.

It may take time to work out the best treatment for you. You may need to try different types or combinations of medicines before you find the most effective ones.

If you find you can’t manage your migraines using over-the-counter medicines, your doctor may prescribe something stronger.

Migraine treatments can help stop symptoms and prevent future attacks.

Many medications have been designed to treat migraines. Some drugs often used to treat other conditions also may help relieve or prevent migraines. Medications used to combat migraines fall into two broad categories:

• Pain-relieving medications. Also known as acute or abortive treatment, these types of drugs are taken during migraine attacks and are designed to stop symptoms.
• Preventive medications. These types of drugs are taken regularly, often on a daily basis, to reduce the severity or frequency of migraines.

Your treatment strategy depends on the frequency and severity of your headaches, the degree of disability your headaches cause, and your other medical conditions.

Some medications aren’t recommended if you’re pregnant or breast-feeding. Some medications aren’t given to children. Your doctor can help find the right medication for you.

During a migraine attack

Most people find that sleeping or lying in a darkened room is the best thing to do when having a migraine attack.

Others find that eating something helps, or they start to feel better once they’ve been sick.

Pain-relieving medications

Take pain-relieving drugs as soon as you experience signs or symptoms of a migraine for the best results. It may help if you rest or sleep in a dark room after taking them. Medications include:

Painkillers

Many people who have migraines find that over-the-counter painkillers, such as paracetamol, aspirin and ibuprofen, can help to reduce their symptoms.

They tend to be most effective if taken at the first signs of a migraine attack, as this gives them time to absorb into your bloodstream and ease your symptoms.

It’s not advisable to wait until the headache worsens before taking painkillers as it’s often too late for the medication to work. Soluble painkillers (tablets you dissolve in a glass of water) are a good alternative because they’re absorbed quickly by your body.

If you can’t swallow painkillers because of nausea or vomiting, suppositories may be a better option. These are capsules that are inserted into the anus (back passage).

Cautions

When taking over-the-counter painkillers, always make sure you read the instructions on the packaging and follow the dosage recommendations.

Children under 16 shouldn’t take aspirin unless it’s under the guidance of a healthcare professional. Aspirin and ibuprofen are also not recommended for adults who have a history of stomach problems, such as stomach ulcers, liver problems or kidney problems.

Taking any form of painkiller frequently can make migraines worse. This is sometimes called “medication overuse headache” or “painkiller headache”.

Speak to your doctor if you find yourself needing to use painkillers repeatedly or if over-the-counter painkillers aren’t effective. Your doctor may prescribe stronger painkillers or recommend using painkillers along with triptans (see below). If they suspect the frequent use of painkillers may be contributing your headaches, they may recommended that you stop using them.

Treatment for pregnant and breastfeeding women

In general, migraine treatment with medicines should be limited as much as possible when you’re pregnant or breastfeeding. Instead, trying to identify and avoid potential migraine triggers is often recommended.

If medication is essential, then your doctor may prescribe you a low-dose painkiller, such as paracetamol. In some cases, anti-inflammatory drugs or triptans may be prescribed. Speak to your doctor or midwife before taking medication when you are pregnant or breastfeeding.

Triptans

If ordinary painkillers aren’t helping to relieve your migraine symptoms, you should make an appointment to see your doctor. They may recommend taking painkillers in addition to a type of medication called a triptan and possibly anti-sickness medication (see below).

• Triptans aren’t recommended for people at risk of strokes and heart attacks.

Triptan medications include sumatriptan (Imitrex), rizatriptan (Maxalt), almotriptan (Axert), naratriptan (Amerge), zolmitriptan (Zomig), frovatriptan (Frova) and eletriptan (Relpax).

Triptan medicines are a specific painkiller for migraine headaches. They’re thought to work by reversing the changes in the brain that may cause migraine headaches.

They cause the blood vessels around the brain to contract (narrow). This reverses the dilating (widening) of blood vessels that’s believed to be part of the migraine process.

Triptans are available as tablets, injections and nasal sprays.

Common side effects of triptans include:

• warm-sensations
• tightness
• tingling
• flushing
• feelings of heaviness in the face, limbs or chest
• reactions at the injection site, nausea, dizziness, drowsiness and muscle weakness.

Some people also experience nausea, dry mouth and drowsiness. These side effects are usually mild and improve on their own.

• As with other painkillers, taking too many triptans can lead to medication overuse headache.

Your doctor will usually recommend having a follow-up appointment once you’ve finished your first course of treatment with triptans. This is so you can discuss their effectiveness and whether you had any side effects.

If the medication was helpful, treatment will usually be continued. If they weren’t effective or caused unpleasant side effects, your doctor may try prescribing a different type of triptan since responses can be highly variable.

Ergots

Ergotamine and caffeine combination drugs (Migergot, Cafergot) are less effective than triptans. Ergots seem most effective in those whose pain lasts for more than 48 hours. Ergots are most effective when taken soon after migraine symptoms start.

Ergotamine may worsen nausea and vomiting related to your migraines, and it may also lead to medication-overuse headaches.

Dihydroergotamine (D.H.E. 45, Migranal) is an ergot derivative that is more effective and has fewer side effects than ergotamine. It’s also less likely to lead to medication-overuse headaches. It’s available as a nasal spray and in injection form.

Anti-sickness medicines

Anti-sickness medicines, known as anti-emetics, can successfully treat migraine in some people even if you don’t experience nausea or vomiting. These are prescribed by your doctor and can be taken alongside painkillers and triptans.

Frequently prescribed medications are chlorpromazine, metoclopramide (Reglan) or prochlorperazine (Compro).

As with painkillers, anti-sickness medicines work better if taken as soon as your migraine symptoms begin. They usually come in the form of a tablet, but are also available as a suppository.

• Side effects of anti-emetics include drowsiness and diarrhea.

Opioid medications

Opioid medications containing narcotics, particularly codeine, are sometimes used to treat migraine pain for people who can’t take triptans or ergots. Narcotics are habit-forming and are usually used only if no other treatments provide relief.

Glucocorticoids (prednisone, dexamethasone)

A glucocorticoid may be used with other medications to improve pain relief. Glucocorticoids shouldn’t be used frequently to avoid side effects.

Combination medicines

You can buy a number of combination medicines for migraine without a prescription at your local pharmacy. These medicines contain both painkillers and anti-sickness medicines. If you’re not sure which one is best for you, ask your pharmacist.

It can also be very effective to combine a triptan with another painkiller, such as ibuprofen.

Many people find combination medicines convenient. However, the dose of painkillers or anti-sickness medicine may not be high enough to relieve your symptoms. If this is the case, it may be better to take painkillers and anti-sickness medicines separately. This allows you to easily control the doses of each.

Preventive medications

You may be a candidate for preventive therapy if:

• You have four or more debilitating attacks a month
• If attacks last more than 12 hours
• If pain-relieving medications aren’t helping
• If your migraine signs and symptoms include a prolonged aura or numbness and weakness

Preventive medications can reduce the frequency, severity and length of migraines and may increase the effectiveness of symptom-relieving medicines used during migraine attacks. It may take several weeks to see improvements in your symptoms.

Your doctor may recommend daily preventive medications, or only when a predictable trigger, such as menstruation, is approaching.

Preventive medications don’t always stop headaches completely, and some drugs cause serious side effects. If you have had good results from preventive medicine and your migraines are well-controlled, your doctor may recommend tapering off the medication to see if your migraines return without it.

The most common medications for migraine prevention include:

• Cardiovascular drugs. Beta blockers, which are commonly used to treat high blood pressure and coronary artery disease, may reduce the frequency and severity of migraines.

The beta blockers propranolol (Inderal LA, Innopran XL, others), metoprolol tartrate (Lopressor) and timolol (Betimol) have proved effective for preventing migraines. Other beta blockers are also sometimes used for treatment of migraine. You may not notice improvement in symptoms for several weeks after taking these medications.

If you’re older than age 60, use tobacco, or have certain heart or blood vessel conditions, doctors may recommend you take a different medication.

Another class of cardiovascular medications (calcium channel blockers) used to treat high blood pressure also may be helpful in preventing migraines and relieving symptoms. Verapamil (Calan, Verelan, others) is a calcium channel blocker that may help prevent migraines with aura.

In addition, the angiotensin-converting enzyme inhibitor lisinopril (Zestril) may be useful in reducing the length and severity of migraines.

• Antidepressants. Tricyclic antidepressants may be effective in preventing migraines, even in people without depression.

Tricyclic antidepressants may reduce the frequency of migraines by affecting the level of serotonin and other brain chemicals. Amitriptyline is the only tricyclic antidepressant proved to effectively prevent migraines. Other tricyclic antidepressants are sometimes used because they may have fewer side effects than amitriptyline.

These medications can cause sleepiness, dry mouth, constipation, weight gain and other side effects.

Another class of antidepressants called selective serotonin reuptake inhibitors hasn’t been proved to be effective for migraine prevention. These drugs may even worsen or trigger headaches.

However, research suggests that one serotonin and norepinephrine reuptake inhibitor, venlafaxine (Effexor XR), may be helpful in preventing migraines.

• Anti-seizure drugs. Some anti-seizure drugs, such as valproate (Depacon) and topiramate (Topamax), seem to reduce the frequency of migraines.

In high doses, however, these anti-seizure drugs may cause side effects. Valproate sodium may cause nausea, tremor, weight gain, hair loss and dizziness. Valproate products should not be used in pregnant women or women who may become pregnant.

Topiramate may cause diarrhea, nausea, weight loss, memory difficulties and concentration problems.

• OnabotulinumtoxinA (Botox). OnabotulinumtoxinA (Botox) has been shown to be helpful in treating chronic migraines in adults.

During this procedure, onabotulinumtoxinA is injected into the muscles of the forehead and neck. When this is effective, the treatment usually needs to be repeated every 12 weeks.

• Pain relievers. Taking nonsteroidal anti-inflammatory drugs, especially naproxen (Naprosyn), may help prevent migraines and reduce symptoms.

Acupuncture

If medication is unsuitable, or it doesn’t help to prevent migraines, you may want to consider acupuncture.

The National Institute for Health and Care Excellence ⁵⁸ states that a course of up to 10 sessions over a five to eight week period may be beneficial.

In a 2016 Cochrane review ⁵⁹ the available evidence suggests that adding acupuncture to symptomatic treatment of migraine attacks reduces the frequency of headaches. The available evidence also suggest that acupuncture may be at least similarly effective as treatment with prophylactic drugs ⁵⁹. Acupuncture can be considered a treatment option for patients willing to undergo this treatment. As for other migraine treatments, long-term studies, more than one year in duration, are lacking.

Transcranial magnetic stimulation

In January 2014, the National Institute for Health and Care Excellence ⁶⁰ approved the use of a treatment called transcranial magnetic stimulation (TMS) for the treatment and prevention of migraines.

Transcranial magnetic stimulation involves holding a small electrical device to your head that delivers magnetic pulses through your skin. It’s not clear exactly how transcranial magnetic stimulation works in treating migraines, but studies have shown that using it at the start of a migraine can reduce its severity. It can also be used in combination with the medications mentioned above without interfering with them.

However, transcranial magnetic stimulation isn’t a cure for migraines and it doesn’t work for everyone. The evidence for its effectiveness isn’t strong and is limited to people who have migraine with aura.

There’s also little evidence about the potential long-term effects of the treatment, although studies into the treatment have so far only reported minor and temporary side effects, including:

• slight dizziness
• drowsiness and tiredness
• a muscle tremor that can make it difficult to stand
• irritability

The National Institute for Health and Care Excellence recommends that transcranial magnetic stimulation should only be provided by headache specialists in specialist centers, because of the uncertainty about the potential long-term side effects. The specialist will keep a record of your experiences using the treatment.

Home remedies for migraine

Self-care measures can help ease migraine pain.

• Practice muscle relaxation exercises. Relaxation techniques may include progressive muscle relaxation, meditation or yoga.
• Get enough sleep, but don’t oversleep. Get the right balance of sleep each night, making sure to go to bed and wake up at consistent times.
• Rest and relax. Try to rest in a dark, quiet room when you feel a headache coming on. Place an ice pack wrapped in a cloth on the back of your neck and apply gentle pressure to painful areas on your scalp.
• Keep a headache diary. Continue recording in your headache diary even after you see your doctor. It will help you learn more about what triggers your migraines and what treatment is most effective.

Alternative medicine

Nontraditional therapies may be helpful if you have chronic migraine pain.

• Biofeedback. Biofeedback appears to be effective in relieving migraine pain. This relaxation technique uses special equipment to teach you how to monitor and control certain physical responses related to stress, such as muscle tension.
• Massage therapy. Massage therapy may help reduce the frequency of migraines. Researchers continue to study the effectiveness of massage therapy in preventing migraines.
• Cognitive behavioral therapy. Cognitive behavioral therapy may benefit some people with migraines. This type of psychotherapy teaches you how behaviors and thoughts affect how you perceive pain.
• Herbs, vitamins and minerals. There is some evidence that the herbs feverfew and butterbur may prevent migraines or reduce their severity, though study results are mixed. Butterbur isn’t recommended because of long-term safety concerns.
• A high dose of riboflavin (vitamin B-2) also may prevent migraines or reduce the frequency of headaches.
• Coenzyme Q10 supplements may decrease the frequency of migraines, but larger studies are needed.
• Due to low magnesium levels in some people with migraines, magnesium supplements have been used to treat migraines, but with mixed results.

Ask your doctor if these treatments are right for you. Don’t use feverfew, riboflavin or butterbur if you’re pregnant or without first talking with your doctor.

Cluster headaches

Cluster headaches are rare headaches that occur in cyclical patterns or clusters. Cluster headaches are excruciating attacks of pain in one side of the head, often felt around the eye. The pain usually peaks 5 to 10 minutes after onset, lasts 15 minutes and can continue at that intensity for up to 3 hours ⁶¹. A cluster headache commonly can awaken you in the middle of the night with intense pain in or around one eye on one side of your head.

Cluster headache affects about 1 per 1000 Americans. Cluster headaches generally begin between the ages of 20 and 50 but may start at any age, occur more often in men than in women, and are more common in smokers than in nonsmokers.

Cluster headaches occur on one side of the face, often around or behind the eye. They can last anywhere between 15 minutes and three hours. They can happen as often as 8 times in one day, or once every couple of days. Many people also have, on the same side of the face:

• a red and weepy eye
• a drooping or swollen eyelid
• a runny or blocked nose
• sweaty skin.

People often feel restless and agitated during an attack because the pain is so intense, and they may react by rocking, pacing, or banging their head against the wall.

People who get them find they have frequent headaches for weeks or months, then none for a long time – a remission period when the headaches stop. During remission, no headaches occur for months and sometimes even years. In a few people, the cluster headaches come on continuously. They happen more in the night than during the day, and often at the same time each night. They are very painful.

Fortunately, cluster headache is rare and not life-threatening. Treatments can make cluster headache attacks shorter and less severe. In addition, medications can reduce the number of cluster headaches.

Seek emergency care

If you have any of these signs and symptoms:

• An abrupt, severe headache, often like a thunderclap
• A headache with a fever, nausea or vomiting, a stiff neck, mental confusion, seizures, numbness, or speaking difficulties, which can indicate a number of problems, including a stroke, meningitis, encephalitis or a brain tumor
• A headache after a head injury, even if it’s a minor fall or bump, especially if it worsens
• A sudden, severe headache unlike any you’ve had
• A headache that worsens over days and changes in pattern

What causes cluster headaches

Nobody knows what causes cluster headaches, but cluster headache patterns suggest that abnormalities in the body’s biological clock (hypothalamus) play a role.

Cluster headaches sometimes run in families. People who get them are more likely to smoke heavily, drink heavily, drink a lot of caffeine and feel a lot of stress, but they can happen to anybody. Further research on risk factors is needed. Studies have shown family history to be a factor and a genetic cause is strongly suggested.

Risk factors for cluster headache

Risk factors for cluster headaches include:

• Sex. Men are more likely to have cluster headaches.
• Age. Most people who develop cluster headaches are between ages 20 and 50, although the condition can develop at any age.
• Smoking. Many people who get cluster headache attacks are smokers. However, quitting smoking usually has no effect on the headaches.
• Alcohol use. Alcohol can trigger an attack if you’re at risk of cluster headache.
• A family history. Having a parent or sibling who has had cluster headache might increase your risk.

Cluster headache triggers

Unlike migraine and tension headache, cluster headache generally isn’t associated with triggers, such as foods, hormonal changes or stress.

During cluster headache periods any substance that dilates blood vessels (such as alcohol, glyceryl trinitrate and histamine) will trigger an attack. That is drinking alcohol may quickly trigger a splitting headache. For this reason, many people with cluster headache avoid alcohol during a cluster period.

Other possible triggers include the use of medications such as nitroglycerin, a drug used to treat heart disease.

Cluster headache symptoms

Common signs and symptoms

Cluster headaches begin quickly and usually without warning. The pain is very severe and is often described as a sharp, burning or piercing sensation on one side of the head. It’s often felt around the eye, temple and sometimes face. It tends to occur on the same side for each attack. Although you might first have migraine-like nausea and aura.

Common signs and symptoms during a cluster headache include:

• Excruciating pain, generally situated in or around one eye, but may radiate to other areas of your face, forehead, temple, neck, shoulders, cheek and upper gum on same side of face
• Steady rather than throbbing pain
• One-sided pain
• Restlessness
• Excessive tearing
• Redness in your eye on the affected side
• Stuffy or runny nose on the affected side
• Forehead or facial sweating
• Pale skin (pallor) or flushing on your face
• Swelling around your eye on the affected side
• Drooping eyelid
• Attacks of 15 – 180 minutes
• 1-3 attacks per day
• Attacks can occur on consecutive days for 6-8 weeks
• Remission periods of months to years
• Onset of pain about an hour after going to bed.

People with cluster headache, unlike those with migraine, are likely to pace or sit and rock back and forth. Some migraine-like symptoms — including sensitivity to light and sound — can occur with a cluster headache, though usually on one side.

Cluster period characteristics

A cluster period generally lasts from six to 12 weeks. The starting date and the duration of each cluster period might be consistent from period to period. For example, cluster periods can occur seasonally, such as every spring or every fall.

Most people have episodic cluster headaches. In episodic cluster headaches, the headaches occur for one week to a year, followed by a pain-free remission period that can last as long as 12 months before another cluster headache develops.

Chronic cluster periods might continue for more than a year, or pain-free periods might last less than one month.

During a cluster period:

• Headaches usually occur every day, sometimes several times a day.
• A single attack can last from 15 minutes to three hours.
• The attacks often occur at the same time each day.
• Most attacks occur at night, usually one to two hours after you go to bed.

The pain usually ends as suddenly as it began, with rapidly decreasing intensity. After attacks, most people are pain-free, but exhausted.

Cluster headache diagnosis

Cluster headache has a characteristic type of pain and pattern of attacks. Your doctor will talk to you and examine you. A diagnosis depends on your description of the attacks, including your pain, the location and severity of your headaches, and associated symptoms.

How often your headaches occur and how long they last also are important factors.

There is no specific test for cluster headache, but your doctor may do tests to rule out other conditions. Your doctor will likely try to pinpoint the type and cause of your headache using certain approaches.

Neurological examination

A neurological examination may help your doctor detect physical signs of a cluster headache. Your doctor will use a series of procedures to assess your brain function, including testing your senses, reflexes and nerves.

Imaging tests

If you have unusual or complicated headaches or an abnormal neurological examination, your doctor might recommend other tests to rule out other serious causes of head pain, such as a tumor or aneurysm. Common brain imaging tests include:

• CT scan. This uses a series of X-rays to create detailed cross-sectional images of your brain.
• Magnetic resonance imaging (MRI). This uses a powerful magnetic field and radio waves to produce detailed images of your brain and blood vessels.

How to get rid of cluster headaches

There’s no cure for cluster headaches and treatment and prevention of cluster headaches can be difficult. The usual painkillers often don’t work.

The goal of treatment is to decrease the severity of pain, shorten the headache period and prevent the attacks.

There are a range of medicines that can help prevent a cluster starting. Talk to your doctor about these.

Because the pain of a cluster headache comes on suddenly and might subside within a short time, cluster headache can be difficult to evaluate and treat, as it requires fast-acting medications.

If you are in the middle of a cluster, you can reduce your chances of having a headache by getting plenty of sleep, and sleeping at the same time each night, and also by avoiding alcohol completely. You should also try to get regular sleep, avoid stress or strenuous physical activity, and avoid a high altitude.

If you get a cluster headache, then you can try:

• medicines – talk to your doctor
• oxygen through a mask
• a nasal spray of local anesthetic.

Talk to your doctor about these.

Some types of acute medication can provide some pain relief quickly. The therapies listed below have proved to be most effective for acute and preventive treatment of cluster headache.

Acute cluster headache treatments

Fast-acting cluster headache medications available from your doctor include:

• Oxygen. Briefly inhaling 100 percent oxygen through a mask at a minimum rate of at least 12 liters a minute provides dramatic relief for most who use it. The effects of this safe, inexpensive procedure can be felt within 15 minutes. Oxygen is generally safe and without side effects. The major drawback of oxygen is the need to carry an oxygen cylinder and regulator with you, which can make the treatment inconvenient and inaccessible at times. Small, portable units are available, but some people still find them impractical.
• Triptans. The injectable form of sumatriptan (Imitrex), which is commonly used to treat migraine, is also an effective treatment for acute cluster headache. The first injection may be given while under medical observation. Some people may benefit from using sumatriptan in nasal spray form, but for most people this isn’t as effective as an injection and it may take longer to work. Sumatriptan isn’t recommended if you have uncontrolled high blood pressure or heart disease.
• Another triptan medication, zolmitriptan (Zomig), can be taken in nasal spray or tablet form for relief of cluster headache. This medication may be an option if you can’t tolerate other forms of fast-acting treatments.
• Octreotide. Octreotide (Sandostatin), an injectable synthetic version of the brain hormone somatostatin, is an effective treatment for cluster headache for some people.
• Local anesthetics. The numbing effect of local anesthetics, such as lidocaine (Xylocaine), may be effective against cluster headache pain in some people when given through the nose (intranasal).
• Dihydroergotamine. The injectable form of dihydroergotamine (D.H.E. 45) may be an effective pain reliever for some people with cluster headache. This medication is also available in an inhaled (intranasal) form called Migranal, but this form hasn’t been proved to be effective for cluster headache.

Preventive cluster headache treatments

Preventive therapy starts at the onset of the cluster episode with the goal of suppressing attacks.

Determining which medicine to use often depends on the length and regularity of your episodes. Under the guidance of your doctor, the drugs can be tapered off once the expected length of the cluster episode ends.

Cluster headache preventive medication

• Calcium channel blockers. The calcium channel blocking agent verapamil (Calan, Verelan, others) is often the first choice for preventing cluster headache. Verapamil may be used with other medications. Occasionally, longer term use is needed to manage chronic cluster headache. Side effects may include constipation, nausea, fatigue, swelling of the ankles and low blood pressure.
• Corticosteroids. Inflammation-suppressing drugs called corticosteroids, such as prednisone, are fast-acting preventive medications that may be effective for many people with cluster headaches. Your doctor may prescribe corticosteroids if your cluster headache condition has started recently or if you have a pattern of brief cluster periods and long remissions. Although corticosteroids might be a good option to use for several days, serious side effects such as diabetes, hypertension and cataracts make them inappropriate for long-term use.
• Lithium carbonate. Lithium carbonate, which is used to treat bipolar disorder, may be effective in preventing chronic cluster headache if other medications haven’t prevented cluster headaches. Side effects include tremor, increased thirst and diarrhea. Your doctor can adjust the dosage to minimize side effects. While you’re taking this medication, your blood will be checked regularly for the development of more-serious side effects, such as kidney damage.
• Nerve block. Injecting a numbing agent (anesthetic) and corticosteroid into the area around the occipital nerve, situated at the back of your head, might improve chronic cluster headaches. An occipital nerve block may be useful for temporary relief until long-term preventive medications take effect.
• Melatonin. Studies in small numbers of people suggest that 10 milligrams of melatonin taken in the evening might reduce the frequency of cluster headache.
• Other preventive medications used for cluster headache include anti-seizure medications, such as topiramate (Topamax, Qudexy XR).

Cluster headache Surgery

Rarely, doctors may recommend surgery for people with chronic cluster headaches who don’t find relief with aggressive treatment or who can’t tolerate the medications or their side effects.

Several small studies found that occipital nerve stimulation on one or both sides may be beneficial. This involves implanting an electrode next to one or both occipital nerves.

Deep brain stimulation is a promising but as yet unproven treatment for cluster headaches that don’t respond to other treatments. Because this involves placing an electrode deep in the brain, there are significant risks, such as an infection or hemorrhage.

Some surgical procedures for cluster headache attempt to damage the nerve pathways thought to be responsible for pain, most commonly the trigeminal nerve that serves the area behind and around your eye.

However, the long-term benefits of destructive procedures are disputed. Also, because of the possible complications — including muscle weakness in your jaw or sensory loss in certain areas of your face and head — it’s rarely considered.

Potential future cluster headache treatments

Researchers are studying a potential treatment called occipital nerve stimulation. In this procedure, your surgeon implants electrodes in the back of your head and connects them to a small pacemaker-like device (generator). The electrodes send impulses to stimulate the area of the occipital nerve, which may block or relieve your pain signals.

Several small studies of occipital nerve stimulation found that the procedure reduced pain in some people with chronic cluster headaches.

Similar research is underway with deep brain stimulation. In this procedure, doctors implant an electrode in the hypothalamus, the area of your brain associated with the timing of cluster periods. Your surgeon connects the electrode to a generator that changes your brain’s electrical impulses and may help relieve your pain.

Deep brain stimulation of the hypothalamus may provide relief for people with severe, chronic cluster headaches that haven’t been successfully treated with medications.

Cluster headache home remedies

The following measures may help you avoid a cluster attack during a cluster cycle:

• Maintaining a regular sleep schedule. Cluster periods can begin when there are changes in your normal sleep schedule. During a cluster period, follow your usual sleep routine.
• Avoid alcohol. Alcohol consumption, including beer and wine, can quickly trigger a headache during a cluster period.
• Taking medication as prescribed.
• Avoiding high stress or strenuous physical activity
• Avoiding high altitude
• Quit smoking.

What causes headaches

Primary Headaches

Primary headaches are the most common. They include tension headaches, migraine and cluster headaches.

Some primary headaches can be triggered by lifestyle factors, including:

• stress
• eye strain or squinting
• poor posture
• dehydration
• drinking too much alcohol or eating certain foods, such as processed meats that contain nitrates or monosodium glutamate (MSG)
• changes in sleep or lack of sleep
• poor posture
• skipping a meal.

Sometimes there is no obvious cause.

A few headache patterns also are generally considered types of primary headache, but are less common. These headaches have distinct features, such as an unusual duration or pain associated with a certain activity.

Although generally considered primary, each could be a symptom of an underlying disease. They include:

• Chronic daily headaches (for example, chronic migraine, chronic tension-type headache, or hemicranias continua)
• Cough headaches
• Exercise headaches
• Sex headaches

Secondary Headaches

Secondary headaches have a separate cause, such as illness. They include headaches caused by drinking too much alcohol or a head injury or concussion.

Headaches in women may be caused by hormones, and some women notice a link between headaches and their periods. Hormonal changes due to taking the Pill, menopause and pregnancy can also be triggers for headaches.

Some headaches can even occur as a side effect of medication, such as painkillers. People sometimes get headaches when they’re unwell. For example, you may get a headache when you have a cold, sinusitis, flu or an allergic reaction.

There are a lot of illnesses that can cause headaches. See your doctor if you are getting more headaches than usual, they are worse or don’t improve with over the counter medicines, or they are stopping you from working or sleeping.

A secondary headache is a symptom of a disease that can activate the pain-sensitive nerves of the head. Any number of conditions — varying greatly in severity — may cause secondary headaches.

Possible causes of secondary headaches include:

• Acute sinusitis
• Arterial tears (carotid or vertebral dissections)
• Blood clot (venous thrombosis) within the brain — separate from stroke
• Brain aneurysm (a bulge in an artery in your brain)
• Brain AVM (brain arteriovenous malformation) — an abnormal formation of brain blood vessels
• Brain tumor
• Carbon monoxide poisoning
• Chiari malformation (structural problem at the base of your skull)
• Concussion
• Dehydration
• Dental problems
• Ear infection (middle ear)
• Encephalitis (brain inflammation)
• Giant cell arteritis (inflammation of the lining of the arteries)
• Glaucoma (acute angle closure glaucoma)
• Hangovers
• High blood pressure (hypertension)
• Influenza (flu) and other febrile (fever) illnesses
• Intracranial hematoma (blood vessel ruptures with bleeding in or around the brain)
• Medications to treat other disorders
• Meningitis (inflammation of the membranes and fluid surrounding your brain and spinal cord)
• Monosodium glutamate (MSG)
• Overuse of pain medication
• Panic attacks and panic disorder
• Post-concussion syndrome
• Pressure from tight headgear, such as a helmet or goggles
• Pseudotumor cerebri (increased pressure inside the skull), also known as idiopathic intracranial hypertension
• Stroke
• Toxoplasmosis
• Trigeminal neuralgia (as well as other neuralgias, all involving irritation of certain nerves connecting the face and brain)

Some types of secondary headaches include:

• External compression headaches (a result of pressure-causing headgear)
• Ice cream headaches (commonly called brain freeze)
• Rebound headaches (caused by overuse of pain medication)
• Sinus headaches (caused by inflammation and congestion in sinus cavities)
• Spinal headaches (caused by low pressure or volume of cerebrospinal fluid, possibly the result of spontaneous cerebrospinal fluid leak, spinal tap or spinal anesthesia)
• Thunderclap headaches (a group of disorders that involves sudden, severe headaches with multiple causes)

Dehydration

Lack of fluids can cause dehydration and is a common cause of headaches. Fluids are needed for the body to function correctly and may be lost through:

• illness such as vomiting or diarrhea
• vigorous exercise
• excessive sweating
• alcohol
• having large amounts of drinks containing caffeine such as coffee, tea or cola, which cause you to urinate frequently
• working in hot weather or high-temperature environments.

If you are getting a lot of headaches or concerned talk to your doctor.

Headache Diagnosis

Evaluation of headache focuses on:

• Determining whether a secondary headache is present
• Checking for symptoms that suggest a serious cause

If no cause or serious symptoms are identified, evaluation focuses on diagnosing primary headache disorders.

History

History of present illness includes questions about headache location, duration, severity, onset (eg, sudden, gradual), and quality (eg, throbbing, constant, intermittent, pressure-like). Exacerbating and remitting factors (eg, head position, time of day, sleep, light, sounds, physical activity, odors, chewing) are noted. If the patient has had previous or recurrent headaches, the previous diagnosis (if any) needs to be identified, and whether the current headache is similar or different needs to be determined. For recurrent headaches, age at onset, frequency of episodes, temporal pattern (including any relationship to phase of menstrual cycle), and response to treatments (including over-the-counter treatments) are noted.

Review of systems should seek symptoms suggesting a cause, including:

• Vomiting: Migraine or increased intracranial pressure
• Fever: Infection (eg, encephalitis, meningitis, sinusitis)
• Red eye and/or visual symptoms (halos, blurring): Acute angle-closure glaucoma
• Visual field deficits, diplopia, or blurring vision: Ocular migraine, brain mass lesion, or idiopathic intracranial hypertension
• Lacrimation and facial flushing: Cluster headache
• Rhinorrhea: Sinusitis
• Pulsatile tinnitus: Idiopathic intracranial hypertension
• Preceding aura: Migraine
• Focal neurologic deficit: Encephalitis, meningitis, intracerebral hemorrhage, subdural hematoma, tumor, or other mass lesion
• Seizures: Encephalitis, tumor, or other mass lesion
• Syncope at headache onset: Subarachnoid hemorrhage
• Myalgias and/or vision changes (in people > 55 yr): Giant cell arteritis

Past medical history should identify risk factors for headache, including exposure to drugs, substances (particularly caffeine), and toxins (see Secondary Headache); recent lumbar puncture; immunosuppressive disorders or IV drug use (risk of infection); hypertension (risk of brain hemorrhage); cancer (risk of brain metastases); and dementia, trauma, coagulopathy, or use of anticoagulants or ethanol (risk of subdural hematoma).

Family and social history should include any family history of headaches, particularly because migraine headache may be undiagnosed in family members.

Physical examination

Vital signs, including temperature, are measured. General appearance (eg, whether restless or calm in a dark room) is noted. A general examination, with a focus on the head and neck, and a full neurologic examination are done.

The scalp is examined for areas of swelling and tenderness. The ipsilateral temporal artery is palpated, and both temporomandibular joints are palpated for tenderness and crepitance while the patient opens and closes the jaw.

The eyes and periorbital area are inspected for lacrimation, flushing, and conjunctival injection. Pupillary size and light responses, extraocular movements, and visual fields are assessed. The fundi are checked for spontaneous venous pulsations and papilledema. If patients have vision-related symptoms or eye abnormalities, visual acuity is measured. If the conjunctiva is red, the anterior chamber and cornea are examined with a slit lamp if possible, and intraocular pressure is measured.

The nares are inspected for purulence. The oropharynx is inspected for swellings, and the teeth are percussed for tenderness.

Neck is flexed to detect discomfort, stiffness, or both, indicating meningismus. The cervical spine is palpated for tenderness.

Red flags

The following findings are of particular concern:

• Neurologic symptoms or signs (eg, altered mental status, weakness, diplopia, papilledema, focal neurologic deficits)
• Immunosuppression or cancer
• Meningismus
• Onset of headache after age 50
• Thunderclap headache (severe headache that peaks within a few seconds)
• Symptoms of giant cell arteritis (eg, visual disturbances, jaw claudication, fever, weight loss, temporal artery tenderness, proximal myalgias)
• Systemic symptoms (eg, fever, weight loss)
• Progressively worsening headache
• Red eye and halos around lights

Interpretation of findings

If similar headaches recur in patients who appear well and have a normal examination, the cause is rarely ominous. Headaches that have recurred since childhood or young adulthood suggest a primary headache disorder. If headache type or pattern clearly changes in patients with a known primary headache disorder, secondary headache should be considered.

Table 6. Matching Red Flag Findings with a Cause for Headache

Suggestive Findings	Causes
Suggestive Findings	Causes
Neurologic symptoms or signs (eg, altered mental status, confusion, neurogenic weakness, diplopia, papilledema, focal neurologic deficits)	Encephalitis, subdural hematoma, subarachnoid or intracerebral hemorrhage, tumor, other intracranial mass, increased intracranial pressure
Immunosuppression or cancer	CNS infection, metastases
Meningismus	Meningitis, subarachnoid hemorrhage, subdural empyema
Onset of headache after age 50	Increased risk of a serious cause (eg, tumor, giant cell arteritis)
Thunderclap headache (severe headache that peaks within a few seconds)	Subarachnoid hemorrhage
Combination of fever, weight loss, visual disturbances, jaw claudication, temporal artery tenderness, and proximal myalgias	Giant cell arteritis
Systemic symptoms (eg, fever, weight loss)	Sepsis, hyperthyroidism, cancer
Progressively worsening headache	Secondary headache
Red eye and halos around lights	Acute angle-closure glaucoma

Tests and Investigations

Most patients can be diagnosed without testing. However, some serious disorders may require urgent or immediate testing. Some patients require tests as soon as possible.

CT (or MRI) should be done as soon as possible in patients with any of the following findings:

• Thunderclap headache
• Altered mental status
• Meningismus
• Papilledema
• Signs of sepsis (eg, rash, shock)
• Acute focal neurologic deficit
• Severe hypertension (eg, systolic > 220 mm Hg or diastolic >120 mm Hg on consecutive readings)

In addition, if meningitis, subarachnoid hemorrhage, or encephalitis is being considered, lumbar puncture and CSF analysis should be done, if not contraindicated by imaging results. Patients with a thunderclap headache require CSF analysis even if CT and examination findings are normal as long as lumbar puncture is not contraindicated by imaging results.

Tonometry should be done if findings suggest acute narrow-angle glaucoma (eg, visual halos, nausea, corneal edema, shallow anterior chamber).

Other testing should be done within hours or days, depending on the acuity and seriousness of findings and suspected causes.

Neuroimaging, usually MRI, should be done if patients have any of the following:

• Focal neurologic deficit of subacute or uncertain onset
• Age > 50 yr
• Weight loss
• Cancer
• HIV infection or AIDS
• Change in an established headache pattern
• Diplopia

New-onset headache after age 50 should be considered a secondary disorder until proven otherwise.

ESR should be done if patients have visual symptoms, jaw or tongue claudication, temporal artery signs, or other findings suggesting giant cell arteritis.

CT of the paranasal sinuses is done to rule out complicated sinusitis if patients have a moderately severe systemic illness (eg, high fever, dehydration, prostration, tachycardia) and findings suggesting sinusitis (eg, frontal, positional headache; epistaxis; purulent rhinorrhea).

Lumbar puncture and CSF analysis are done if headache is progressive and findings suggest idiopathic intracranial hypertension (eg, transient obscuration of vision, diplopia, pulsatile intracranial tinnitus) or chronic meningitis (eg, persistent low-grade fever, cranial neuropathies, cognitive impairment, lethargy, vomiting).

How to get rid of a headache

There’s no single treatment for headaches because so many potential causes exist. Treatment is directed at the underlying cause of the headaches — if one is found.

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