What is indigestion or dyspepsia ?

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What is indigestion or dyspepsia ?

What is indigestion or dyspepsia ?

Dyspepsia or indigestion is a pain or an uncomfortable feeling in the upper middle part of your stomach ¹⁾. Dyspepsia is not a condition, it is a symptom complex ²⁾. Dyspepsia can be defined as persistent or recurrent abdominal pain or abdominal discomfort centered in the upper abdomen ³⁾. This discomfort may include symptoms of nausea, vomiting, early satiety, postprandial fullness, and upper abdominal bloating. Symptoms are typically associated with eating but not with bowel movements. Heartburn and acid regurgitation are often included as symptoms of dyspepsia; yet if these are the main symptoms, the patient should be considered to have reflux rather than dyspepsia. Patients with symptoms or signs typical of biliary tract or pancreatic disease should not be considered to have dyspepsia or indigestion ⁴⁾.

People of any age can get dyspepsia (indigestion). Both men and women get it. About 1 of every 4 persons gets dyspepsia (indigestion) at some time.

Dyspepsia affects up to 40 percent of adults each year and is often diagnosed as functional (nonulcer) dyspepsia ⁵⁾. The defining symptoms are after meal fullness, early satiation, or epigastric pain or burning in the absence of causative structural disease. These symptoms may coexist with symptoms of functional gastrointestinal disorders, such as gastroesophageal reflux (GERD) and irritable bowel syndrome (IBS), as well as anxiety and depression ⁶⁾.

Most cases in patients who seek care are eventually diagnosed as functional dyspepsia ⁷⁾.

Functional (nonulcer) dyspepsia is defined as the presence of postprandial fullness, early satiation, or epigastric pain or burning in the absence of causative structural disease (Table 1) ⁸⁾, ⁹⁾.

Indigestion (dyspepsia) often occurs during or right after eating. It may feel like ¹⁰⁾:

Heat, burning, or pain in the area between the navel and the lower part of the breastbone
Unpleasant fullness that starts soon after a meal begins or when the meal is over

The pain might come and go, but it’s usually there most of the time.

You may also feel nauseated, or even throw up, but bloating and nausea are less common symptoms.

Indigestion is NOT the same as heartburn.

Recent guidelines distinguish dyspepsia from heartburn and gastroesophageal reflux symptoms, which often coincide with dyspepsia but are considered separate entities ¹¹⁾. Previous studies have used a variety of definitions for dyspepsia. As a result, further research is needed to better differentiate functional dyspepsia from other diseases of the gastrointestinal (GI) tract.

The Rome III working group defined functional dyspepsia as the presence of symptoms thought to originate in the gastroduodenal region, in the absence of any organic, systemic, or metabolic disease that is likely to explain them ¹²⁾. Symptoms should be present for a minimum of 3 months; however, symptoms for greater than 6 months are typical.

To facilitate this research, the Rome III diagnostic criteria divide functional dyspepsia into two subcategories ¹³⁾:

Epigastric Pain Syndrome (i.e., epigastric pain or burning) and
Postprandial Distress Syndrome (i.e., postprandial fullness or early satiation).

Table 1. Rome III Diagnostic Criteria for Functional Dyspepsia

Presence of at least one of the following:
	Bothersome postprandial fullness
	Early satiation
	Epigastric pain
	Epigastric burning
	and No evidence of structural disease (including at upper endoscopy) that is likely to explain the symptoms
[Source ¹⁴⁾]

When to Contact a Medical Professional

It can be hard to tell a chest pain from dyspepsia or indigestion from a heart attack.

Get medical help right away if your symptoms include jaw pain, chest pain, back pain, heavy sweating, anxiety, or a feeling of impending doom. These are possible heart attack symptoms.

The symptoms of a heart attack can vary from person to person.

If you think you or someone else is having a heart attack, even if you’re not sure, don’t feel embarrassed to call your local emergency number right away !
Quick Action Can Save Your Life !
Don’t Wait–Get Help Quickly
Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room. Take a nitroglycerin pill if your doctor has prescribed this type of treatment.

What You Must Do If You Have Chest Pain ?

ALL patients suffering from chest pain must have thorough cardiac evaluations to ensure they do not have heart disease prior to being labeled as having dyspepsia or indigestion chest pain.

See your physician if:

Your indigestion symptoms change noticeably.
Your symptoms last longer than a few days.
You have unexplained weight loss.
You have sudden, severe abdominal pain.
You have trouble swallowing.
You have yellow coloring of the skin and eyes (jaundice).
You vomit blood or pass blood in the stool.

Causes indigestion or dyspepsia

There is no definitive pathophysiologic mechanism for functional dyspepsia, which suggests that it is a mixed group of disorders. Patients with functional dyspepsia commonly have coexisting symptoms of irritable bowel syndrome (IBS) or other functional gastrointestinal disorders ¹⁵⁾. In one 10-year follow-up study of patients with dyspepsia or irritable bowel syndrome (IBS), 40 percent of symptomatic patients switched subgroups over the study period ¹⁶⁾.

Several studies implicate impaired stomach muscle motility (dysmotility) as a possible cause of functional dyspepsia ¹⁷⁾, ¹⁸⁾, ¹⁹⁾. Many patients experience motility-related symptoms, such as bloating, early satiation, nausea, and vomiting. Studies have documented altered gastric motility (e.g., gastroparesis, gastric dysrhythmias, abnormal fundus accumulation, pyloric sphincter dysfunction) in up to 80 percent of patients with functional dyspepsia ²⁰⁾, ²¹⁾. However, the degree of dysmotility does not correlate with symptoms ²²⁾, ²³⁾, ²⁴⁾.

Because many patients with functional dyspepsia have burning pain that is indistinguishable from ulcer-related dyspepsia, the relationship between functional dyspepsia and acid secretion is unclear. One study demonstrated a lower pH level in the duodenum of patients with functional dyspepsia compared with those in the control group, although the pH level did not correlate with symptoms ²⁵⁾. The role of Helicobacter pylori infection in functional dyspepsia has also been investigated. Large population studies have shown an increased incidence of Helicobacter pylori infection in patients with functional dyspepsia; however, given the high incidence of both conditions in the general population and the minimal response to treatment, the significance of the association is unclear ²⁶⁾. In spite of this uncertainty, testing for and treating H. pylori infection have become integral to the diagnostic management of functional dyspepsia.

Indigestion may be triggered by:

Drinking too much alcohol
Eating spicy, fatty, or greasy foods
Eating too much (overeating)
Eating too fast
Stress or being nervous
Eating high-fiber foods
Smoking tobacco
Drinking too many caffeinated beverages.

Most of the time, indigestion is not a sign of a serious health problem unless it occurs with other symptoms. These may include:

Bleeding
Weight loss
Trouble swallowing

Rarely, the discomfort of a heart attack is mistaken for indigestion.

Other causes of indigestion are ²⁷⁾:

Coronary heart disease (coronary artery disease): symptoms described as gas or indigestion rather than chest pain by some patients. May have exertional component. Cardiac risk factors.
Gastroesophageal reflux disease (GERD): Heartburn, sometimes reflux of acid or stomach contents into mouth. Symptoms sometimes triggered by lying down and relief with antacids
Achalasia: this problem is caused by damage to the nerves of the esophagus. It is characterized by insufficient lower esophageal sphincter relaxation and loss of esophageal peristalsis. This results in patients’ complaints of dysphagia to solids and liquids, regurgitation, and occasional chest pain with or without weight loss ²⁸⁾.
Gastritis (when the lining of the stomach becomes inflamed or swollen)
Esophageal spasm (substernal chest pain with or without dysphagia for liquids and solids)
Delayed gastric emptying (caused by diabetes, viral illness, or drugs)
Ulcers (stomach or intestinal ulcer): burning or gnawing pain relieved by food or antacids.
Use of certain medicines such as antibiotics, bisphosphonates, erythromycin, iron, estrogen, potassium, aspirin, and over-the-counter pain medicines NSAIDs (Nonsteroidal Anti-inflammatory Drugs). Traditional NSAIDs include aspirin, ibuprofen (Advil, Motrin, etc.), naproxen (e.g., Aleve) and many other generic and brand name drugs ²⁹⁾. Celecoxib (Celebrex) belongs to a newer class of NSAIDs, which doctors call a “COX-2 inhibitor.”
Swelling of the pancreas (pancreatitis)
Gallstones
Cancer (eg, esophageal cancer, stomach cancer): Chronic, vague discomfort. Later, dysphagia (esophageal) or early satiety (gastric) and weight loss.

Gastroesophageal reflux disease (GERD)

Gastroesophageal reflux disease (GERD), defined as symptoms or tissue damage that result from reflux of gastric contents into the esophagus ³⁰⁾, can present with epigastric pain/discomfort although typically heartburn and regurgitation are more common symptoms. While approximately 40% of the US population has intermittent heartburn symptoms at least once monthly, the prevalence of GERD is 14% ³¹⁾. The prevalence of gastroesophageal reflux disease (GERD) in Europe ranges from 10 to 20%, while Asia has a much lower prevalence of 2–5% ³²⁾. There are two patterns of acid reflux: upright (daytime) and supine (nocturnal) ³³⁾. Daytime or upright reflux commonly manifests as postprandial heartburn and may be associated with postprandial regurgitation. These symptoms are usually brief due to rapid clearance of gastric acid from the esophagus. Nocturnal GERD occurs when gastric contents reflux into the esophagus while a patient is recumbent. Approximately 80% of patients with GERD have nocturnal symptoms ³⁴⁾. The increased quantity, duration, and lack of clearance of gastric refluxate at night carry an increased risk of complications. GERD is usually a clinical diagnosis elicited by patient history and asking directed questions.

Peptic ulcer disease

Ulcers are found in approximately 10% of patients undergoing evaluation for dyspepsia ³⁵⁾. Until recently, chronic peptic ulcer disease was almost exclusively due to H. pylori infection with up to 90% of duodenal ulcers and 70% of gastric ulcers attributed to this bacterium ³⁶⁾. However, NSAIDs and aspirin are now responsible for most ulcer disease in developed countries ³⁷⁾. This paradigm shift appears to be due to advances in public health and sanitation as well as effective treatment regimens for H. pylori ³⁸⁾. Yet the combination of H. pylori infection and NSAID usage is synergistic with the risk of uncomplicated peptic ulcer disease estimated to be 17.5 times higher among H. pylori-positive NSAID users compared to H. pylori-negative non-users and a three- to four-fold increase in ulcer incidence with either risk factor alone ³⁹⁾.

Table 2. Causes of indigestion (dyspepsia) and their prevalence

[Source ]

Table 3. List of Agents or Medications That Commonly Cause Dyspepsia

Acarbose (Precose)
Alcohol
Antibiotics, oral (e.g., erythromycin)
Bisphosphonates
Corticosteroids (e.g., prednisone)
Herbs (e.g., garlic, ginkgo, saw palmetto, feverfew, chaste tree berry, white willow)
Iron
Metformin (Glucophage)
Miglitol (Glyset)
Nonsteroidal anti-inflammatory drugs, including cyclooxygenase-2 inhibitors
Opiates
Orlistat (Xenical)
Potassium chloride
Theophylline

Symptoms of indigestion or dyspepsia

Signs and symptoms of nonulcer stomach pain may include:

A burning sensation or discomfort in your upper abdomen or lower chest, sometimes relieved by food or antacids
Bloating
Belching or burping
An early feeling of fullness when eating
Nausea

Seek immediate medical attention if you experience:

Bloody vomit
Dark, tarry stools
Shortness of breath
Pain that radiates to your jaw, neck or arm

Diagnosis of indigestion or dyspepsia

Functional dyspepsia is a diagnosis of exclusion; therefore, physicians should focus on excluding serious or specifically treatable diseases, without spending too much time investigating symptoms. Dyspepsia has a broad and diverse causes (Table 2 and 3), including functional dyspepsia, peptic ulcer disease, reflux esophagitis, and gastric or esophageal malignancy. Functional dyspepsia is the most prevalent diagnosis, making up 70 percent of dyspepsia cases ⁴¹⁾.

Medical History

History of present illness should elicit a clear description of the symptoms, including whether they are acute or chronic and recurrent. Other elements include timing and frequency of recurrence, any difficulty swallowing, and relationship of symptoms to eating or taking drugs. Factors that worsen symptoms (particularly exertion, certain foods, or alcohol) or relieve them (particularly eating or taking antacids) are noted.

Review of systems seeks concomitant GI symptoms such as anorexia, nausea, vomiting, hematemesis, weight loss, and bloody or black (melanotic) stools. Other symptoms include dyspnea and diaphoresis.

Past medical history should include known GI and cardiac diagnoses, cardiac risk factors (eg, hypertension, hypercholesterolemia), and the results of previous tests that have been done and treatments that have been tried. Drug history should include prescription and illicit drug use as well as alcohol.

Physical examination

Your doctor will likely review your signs and symptoms and perform a physical examination.

A number of diagnostic tests may help your doctor determine the cause of your discomfort. These may include:

Blood tests. Blood tests may help rule out other diseases that can cause signs and symptoms similar to those of nonulcer stomach pain.
Tests for a bacterium. Your doctor may recommend a test to look for a bacterium called Helicobacter pylori (H. pylori) that can cause stomach problems. H. pylori testing may use your blood, stool or breath.
Using a scope to examine your digestive system. A thin, flexible, lighted instrument (endoscope) is passed down your throat so that your doctor can view your esophagus, stomach and the first part of your small intestine (duodenum).

Several strategies have been suggested for initial management of uninvestigated dyspepsia, including a trial of acid suppressants, a test-and-treat approach (for H. pylori infection), and early endoscopy. A Cochrane review found that in the absence of warning signs for serious disease, a test-and-treat strategy is effective and cheaper than initial endoscopy ⁴²⁾. Initial endoscopy has been shown to provide a small reduction in the risk of recurrent dyspepsia symptoms; however, physicians need to weigh the cost of endoscopy against patient preference for early reassurance and symptom reduction ⁴³⁾. The Cochrane review showed the test-and-treat strategy to be slightly more effective than empiric acid suppressants, although the comparative cost-effectiveness of these strategies has not been established. Physicians can diagnose H. pylori infection with noninvasive tests, such as serologic, stool antigen, or urea breath tests. Serologic testing is the most common because of its wide availability and low cost, although urea breath testing is more accurate ⁴⁴⁾.

In patients 55 years or younger, the American Gastroenterological Association ⁴⁵⁾ identifies several warning signs that should trigger an early, aggressive workup:

Unintended weight loss,
Progressive dysphagia (difficulty swallowing),
Persistent vomiting,
Evidence of GI bleeding,
Family history of cancer.

The American Gastroenterological Association recommends proceeding directly to endoscopy in patients with warning signs and in those older than 55 years ⁴⁶⁾; however, there has been debate about a lower cutoff age of 35 to 45 years in men ⁴⁷⁾. Although it is not addressed in the American Gastroenterological Association guidelines, an initial complete blood count may be appropriate to screen for anemia. The American Gastroenterological Association guidelines do not address laboratory testing and imaging; however, it is reasonable to consider these approaches in patients with negative esophagogastroduodenoscopy findings and warning signs, or if the treatment course is unsuccessful.

Treatment of indigestion or dyspepsia

Treatment of functional dyspepsia can be frustrating for physicians and patients because few treatment options have proven effective. Patients will need continued reassurance and support from their physicians. Treatment is generally aimed at one of the presumed underlying etiologies of functional dyspepsia.

Gastric Acid Suppression

Gastric acid suppressants have been studied extensively in the treatment of functional dyspepsia. Although their benefit in patients with ulcer-related dyspepsia or gastroesophageal reflux disease is considerable, the benefit in patients with functional dyspepsia is less clear. Antacids, sucralfate (Carafate), and misoprostol (Cytotec) have been evaluated in limited studies without evidence of benefit ⁴⁸⁾. Bismuth salts showed some benefit compared with placebo in a meta-analysis; however, the studies that showed benefit were not well designed and involved only patients with Helicobacter pylori infection, with intent to eradicate the infection. Because of the questionable benefit and long-term risk of neurotoxicity, bismuth salts cannot be recommended as first-line agents for functional dyspepsia ⁴⁹⁾.

Histamine H2 blockers are more promising agents for treating functional dyspepsia and have been evaluated in multiple trials. A meta-analysis concluded that H2 blockers significantly improve symptoms; however, there was evidence of some publication bias, and the effect may have been overestimated, especially in comparison with proton pump inhibitors ⁵⁰⁾. Studies of proton pump inhibitors have shown a statistically significant improvement in symptoms of functional dyspepsia compared with placebo. These studies were of better quality than those investigating H2 blockers, making it difficult to compare relative effectiveness ⁵¹⁾. Given the small benefit of gastric acid suppressants and the commonly chronic nature of functional dyspepsia symptoms, physicians must consider the cost and long-term safety profile of the medication chosen for initial treatment.

Prokinetics

Many patients with functional dyspepsia report predominant symptoms of bloating, early satiation, nausea, and vomiting. As a result, physicians have tried targeting treatment at improving GI motility. Multiple randomized controlled trials have demonstrated that prokinetic agents are effective in treating functional dyspepsia ⁵²⁾. However, the quality of these studies is questionable, and the effectiveness of the agents may have been overestimated. The trials showing effectiveness tended to be targeted at patients with symptoms suggestive of motility disorders, raising the question of their effectiveness in cases of isolated epigastric pain. Also, most studies showing effectiveness used cisapride, which has since been removed from the U.S. market by the U.S. Food and Drug Administration (FDA) because of concerns about cardiac arrhythmias ⁵³⁾. One study has shown that domperidone is effective for functional dyspepsia ⁵⁴⁾. However due to the serious risks associated with domperidone include cardiac arrhythmias, cardiac arrest, and sudden death, the FDA has not approved its use in humans ⁵⁵⁾.

The only available prokinetic agents in the United States are metoclopramide (Reglan) and erythromycin, for which the evidence is sparse. Metoclopramide may cause tardive dyskinesia and parkinsonian symptoms in older persons, limiting its use ⁵⁶⁾. Erythromycin has some prokinetic effects and is used to treat gastroparesis. However, erythromycin has not been studied as a treatment for functional dyspepsia, so its effectiveness is unknown. There is some initial evidence to suggest that herbal formulations containing peppermint improve functional dyspepsia symptoms, possibly through effects on the smooth muscle of the intestines ⁵⁷⁾, ⁵⁸⁾.

Peppermint oil

Peppermint oil (Mentha piperita) is easily available organic oil. The herb peppermint, a natural cross between two types of mint, water mint (Mentha aquatica) and spearmint (Mentha spicata), that grows throughout Europe and North America ⁵⁹⁾. Both peppermint leaves and the essential oil from peppermint have been used for health purposes. Peppermint oil, which is extracted from the stem, leaves, and flowers of the plant, has become popular as a treatment for a variety of conditions, including irritable bowel syndrome (IBS), headache, and non-ulcer dyspepsia

Peppermint oil has been studied most extensively for irritable bowel syndrome (IBS). Results from several studies indicate that peppermint oil in enteric-coated capsules may improve IBS symptoms ⁶⁰⁾.
A few studies have indicated that peppermint oil, in combination with caraway oil, may help relieve indigestion ⁶¹⁾, ⁶²⁾, but this evidence is preliminary and the product that was tested is not available in the United States ⁶³⁾. A meta-analysis of several trials of a preparation containing peppermint and caraway oils plus other herbal extracts (Iberogast) found it to be effective in the treatment of functional dyspepsia ⁶⁴⁾. This benefit may be the result of the preparation’s relaxing effect on the lower esophageal sphincter, with concomitant equalization of pressure between stomach and esophagus and reduced sensation of bloating and abdominal pressure. However, this effect theoretically could result in reflux symptoms in patients predisposed to gastroesophageal reflux. Because multiple herbs were used in these trials, it is difficult to draw definitive conclusions about the specific effects of peppermint in this condition.

Table 4. Key Points About Peppermint Oil

Effectiveness	Irritable bowel syndrome symptoms: probably effective Non-ulcer dyspepsia: probably effective Reducing spasm during gastrointestinal procedures: probably effective Tension headache: probably effective
Adverse effects	Common: allergic reactions, heartburn, perianal burning, blurred vision, nausea, and vomiting Rare: interstitial nephritis, acute renal failure
Interactions	May inhibit the cytochrome P450 1A2 system
Contraindications	Hiatal hernia, severe gastroesophageal reflux, gallbladder disorders; use with caution in pregnant and lactating women
Dosage	Adults: 0.2 to 0.4 mL of oil three times daily in enteric-coated capsules Children older than eight years: 0.1 to 0.2 mL three times daily
Cost	$24 to $32 for one-month supply
Bottom line	Safe at proper dosages and moderately effective in patients with functional gastrointestinal conditions. Peppermint oil should only be used at the recommended doses because significant toxicity can occur at higher doses. Even the recommended medicinal doses of peppermint oil should not be used in infants or very young children, or in women who are pregnant or lactating.

[Source ]

Helicobacter Pylori Eradication

H. pylori eradication may be beneficial as an initial strategy for management of uninvestigated dyspepsia before endoscopy. Several meta-analyses have examined eradication therapy in patients with endoscopically confirmed functional dyspepsia ⁶⁶⁾. Although there have been some discrepancies between studies, the most recent meta-analysis showed a small but statistically significant improvement in functional dyspepsia symptoms with H. pylori eradication ⁶⁷⁾. The number needed to treat for one patient to have relief of symptoms is 15. It is not known whether this strategy is cost-effective ⁶⁸⁾, ⁶⁹⁾.

Psychotropic and Psychological Interventions

Like the other functional gastrointestinal disorders, patients with non-ulcer dyspepsia do report higher levels of psychological distress as well as higher rates of anxiety and depression. The question remains as to whether the psychiatric distress is the cause of the non-ulcer dyspepsia or rather promotes health care–seeking behavior. Psychological and psychiatric interventions are being investigated in non-ulcer dyspepsia, although, once again, clinical trial data are not yet available.

Because of the high rate of coexisting depression and psychiatric illness in patients with refractory functional dyspepsia, many physicians prescribe antidepressants. However, there are only limited studies with a lack of randomized controlled trials supporting this strategy. A meta-analysis showed that tricyclic antidepressants significantly improved functional GI disorders, but the review did not isolate functional dyspepsia from other functional GI disorders, such as irritable bowel syndrome and heartburn ⁷⁰⁾. A small crossover study found that low-dose amitriptyline improved functional dyspepsia symptoms; however, it included only 14 patients and lasted only one month ⁷¹⁾. A larger study of children with irritable bowel syndrome, functional abdominal pain, or functional dyspepsia showed no improvement with amitriptyline versus placebo ⁷²⁾. More trials are underway that may elucidate the use of tricyclic antidepressants in patients with functional dyspepsia ⁷³⁾.

Four randomized controlled trials investigated the use of psychological interventions in patients with dyspepsia symptoms ⁷⁴⁾. Because each trial evaluated a different intervention (i.e., psychotherapy, psychodrama, cognitive behavior therapy, relaxation therapy, and hypnosis), no meta-analysis was possible. Additionally, because of the poor quality of these trials, there was insufficient evidence to recommend these interventions for treatment of dyspepsia. However, these methods can still be used to treat common psychiatric comorbidities.

Home Remedy

Changing the way you eat may help your symptoms. Steps you can take include:

If you smoke, stop smoking.
Allow enough time for meals.
Chew food carefully and completely.
If some foods bother your stomach, try to avoid eating them.
Avoid arguments during meals.
Avoid excitement or exercise right after a meal.
Relax and get rest if indigestion is caused by stress.
If you have acid reflux, don’t eat right before bedtime. Raising the head of your bed with blocks under two legs may also help.

Unless your doctor tells you otherwise, don’t take a lot of anti-inflammatory medicines like ibuprofen (one brand: Motrin), aspirin, naproxen (brand name: Aleve) and ketoprofen (brand name: Orudis) and other NSAIDs. However if you must take them, do so on a full stomach. Acetaminophen (brand name: Tylenol) is a better choice for pain, because it doesn’t hurt your stomach.

Antacids may relieve indigestion.

Medicines you can buy without a prescription, such as ranitidine (Zantac) and omeprazole (Prilosec OTC) can relieve symptoms. Your health care provider may also prescribe these medicines in higher doses or for longer periods of time.

References [ + ]

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