Abdominal distension is a sensation of elevated abdominal pressure and volume. It is estimated that close to 25% of the US population has some degree of abdominal distension on a regular basis. Some describe it as belching, others claim they feel nausea

Nausea

Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...

 and yet others say they pass excessive gas

Flatulence

Flatulence is the expulsion through the rectum of a mixture of gases that are byproducts of the digestion process of mammals and other animals. The medical term for the mixture of gases is flatus, informally known as a fart, or simply gas...

. Abdominal bloating is a sensation of feeling uncomfortably full and the presence of abdominal rumbling sounds. Abdominal distension is not associated with pain but mild cramp

Cramp

Cramps are unpleasant, often painful sensations caused by muscle contraction or over shortening. Common causes of skeletal muscle cramps include muscle fatigue, low sodium, and low potassium...

s may occur.

Causes

Experts believe that the major cause of abnormal bloating is excessive eating, and sleep swallowing

Swallowing

Swallowing, known scientifically as deglutition, is the process in the human or animal body that makes something pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. If this fails and the object goes through the trachea, then choking or pulmonary aspiration...

 or what is known as aerophagia

Aerophagia

Aerophagia is a condition that occurs when a person swallows too much air, which goes to the stomach. It causes abdominal bloating and frequent belching and may cause pain.-Causes:...

. Other causes of bloating are irritable bowel syndrome

Irritable bowel syndrome

Irritable bowel syndrome is a diagnosis of exclusion. It is a functional bowel disorder characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits in the absence of any detectable organic cause. In some cases, the symptoms are relieved by bowel movements...

, diabetes

Diabetes mellitus

Diabetes mellitus, often simply referred to as diabetes, is a group of metabolic diseases in which a person has high blood sugar, either because the body does not produce enough insulin, or because cells do not respond to the insulin that is produced...

, functional dyspepsia

Dyspepsia

Dyspepsia , also known as upset stomach or indigestion, refers to a condition of impaired digestion. It is a medical condition characterized by chronic or recurrent pain in the upper abdomen, upper abdominal fullness and feeling full earlier than expected when eating...

 or transient constipation

Constipation

Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation...

. In rare cases, bloating may occur in individuals who have milk intolerance (lactose intolerance), parasite

Parasitism

Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...

 infection

Infection

An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...

s like giardia

Giardia

Giardia is a genus of anaerobic flagellated protozoan parasites of the phylum Metamonada in the supergroup "Excavata" that colonise and reproduce in the small intestines of several vertebrates, causing giardiasis, commonly known as Beaver fever...

, food poisoning (bacteria

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

), celiac disease, severe peptic ulcer

Peptic ulcer

A peptic ulcer, also known as PUD or peptic ulcer disease, is the most common ulcer of an area of the gastrointestinal tract that is usually acidic and thus extremely painful. It is defined as mucosal erosions equal to or greater than 0.5 cm...

 disease, bowel obstruction

Bowel obstruction

Bowel obstruction is a mechanical or functional obstruction of the intestines, preventing the normal transit of the products of digestion. It can occur at any level distal to the duodenum of the small intestine and is a medical emergency...

 or after certain types of abdominal surgery

Abdominal surgery

The term abdominal surgery broadly covers surgical procedures that involve opening the abdomen. Surgery of each abdominal organ is dealt with separately in connection with the description of that organ Diseases affecting the abdominal cavity are dealt with generally under their own names The term...

. Heart failure and cirrhosis

Cirrhosis

Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...

 are also a common cause of distension. In both of these disorders, fluid accumulates in the abdomen and creates a sensation of fullness. Women are more prone to bloating and often complain about these symptoms during menstruation

Menstruation

Menstruation is the shedding of the uterine lining . It occurs on a regular basis in sexually reproductive-age females of certain mammal species. This article focuses on human menstruation.-Overview:...

.
It is believed that individuals who develop distension either have poor motility

Motility

Motility is a biological term which refers to the ability to move spontaneously and actively, consuming energy in the process. Most animals are motile but the term applies to single-celled and simple multicellular organisms, as well as to some mechanisms of fluid flow in multicellular organs, in...

 of their intestine

Intestine

In human anatomy, the intestine is the segment of the alimentary canal extending from the pyloric sphincter of the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine...

s or are hypersensitive

Hypersensitivity

Hypersensitivity refers to undesirable reactions produced by the normal immune system, including allergies and autoimmunity. These reactions may be damaging, uncomfortable, or occasionally fatal. Hypersensitivity reactions require a pre-sensitized state of the host. The four-group classification...

 to gut sensations.
Experts believe that in most cases, the combination of swallowed air and fluid in the abdomen creates a swirling sensation in the bowels that leads to bloating. Moreover, when the intestines are swollen with air, they push up against the diaphragm and can induce a sensation of pressure in the lower chest.
Studies have shown that swallowing air during eating or delayed emptying of the stomach from hyperacidity

Hyperacidity

Hyperacidity, also known as acid dyspepsia is the condition of excreting more than the normal amount of hydrochloric acid in the stomach.Some causes for hyperacidity are peptic ulcers, gastroesophageal reflux disease, stomach cancer and certain types of diet that contains spicy food.Hyperacidity or...

 leads to bloating after a meal. Individuals who are constipated also complain of bloating. In some individuals who are hypersensitive, any volume of air may be perceived as fullness and there may not be actual abdominal distension.
In some individuals with abdominal bloating, there may be an increasing abdominal girth either from fluid or air accumulation.

Abdominal distension (or "distended abdomen") can be a sign of many other conditions, including:

• Coeliac disease
  Coeliac disease
  Coeliac disease , is an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward...
  
  
• Tropical sprue
  Tropical sprue
  Tropical sprue is a malabsorption disease commonly found in the tropical regions, marked with abnormal flattening of the villi and inflammation of the lining of the small intestine.It differs significantly from coeliac sprue.-Symptoms and signs:...
  
  
• Small bowel bacterial overgrowth syndrome
  Small bowel bacterial overgrowth syndrome
  Small bowel bacterial overgrowth syndrome , or small intestinal bacterial overgrowth , also termed bacterial overgrowth; is a disorder of excessive bacterial growth in the small intestine. Unlike the colon , which is rich with bacteria, the small bowel usually has less than 104 organisms per...
  
  
• Kwashiorkor
  Kwashiorkor
  Kwashiorkor is an acute form of childhood protein-energy malnutrition characterized by edema, irritability, anorexia, ulcerating dermatoses, and an enlarged liver with fatty infiltrates. The presence of edema caused by poor nutrition defines kwashiorkor...
  
  
• Eosinophilic gastroenteritis
  Eosinophilic gastroenteritis
  Eosinophilic gastroenteritis is a rare and heterogeneous condition characterized by patchy or diffuse eosinophilic infiltration of gastrointestinal tissue, first described by Kaijser in 1937...
  
  
• Giardiasis
  Giardiasis
  Giardiasis or beaver fever in humans is a diarrheal infection of the small intestine by a single-celled organism Giardia lamblia. Giardiasis occurs worldwide with a prevalence of 20–30% in developing countries. In the U.S., 20,000 cases are reported to the CDC annually, but the true annual...
  
  
• Strongyloidiasis
  Strongyloidiasis
  Strongyloidiasis is a human parasitic disease caused by the nematode Strongyloides stercoralis, or sometimes S. fülleborni. It can cause a number of symptoms in people, principally skin symptoms, abdominal pain, diarrhea and weight loss...
  
  
• Coccidiosis
• Capillaria philippinensis
  Capillaria philippinensis
  Capillaria philippinensis is a parasitic nematode which causes intestinal capillariasis. This sometimes fatal disease was first discovered in Northern Luzon, Philippines in 1964. Cases have also been reported from China, Egypt, Indonesia, Iran, Japan, Korea, Lao PDR, Taiwan and Thailand...
  
  
• Hookworm Disease
  Hookworm disease
  Hookworm disease is a cutaneous condition characterized by skin lesions that are erythematous macules and papules. Specific types include:* Ancylostomiasis* Necatoriasis...
  
  
• Whipple's disease
  Whipple's disease
  Whipple's disease is a rare, systemic infectious disease caused by the bacterium Tropheryma whipplei. First described by George Hoyt Whipple in 1907 and commonly considered a gastrointestinal disorder, Whipple's disease primarily causes malabsorption but may affect any part of the body including...
  
  
• Ascites
  Ascites
  Ascites is a gastroenterological term for an accumulation of fluid in the peritoneal cavity.The medical condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy. Although most commonly due to cirrhosis and severe liver...
  
  
• Diverticulitis
  Diverticulitis
  Diverticulitis is a common digestive disease particularly found in the large intestine. Diverticulitis develops from diverticulosis, which involves the formation of pouches on the outside of the colon...
  
  
• Fasciolosis
• Kidney stone
  Kidney stone
  A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine...
  
  s
• Lactose intolerance
  Lactose intolerance
  Lactose intolerance, also called lactase deficiency or hypolactasia, is the inability to digest and metabolize lactose, a sugar found in milk...
  
  
• Obstructed bowel
• Polycystic liver disease
  Polycystic liver disease
  Polycystic liver disease usually describes the presence of multiple cysts scattered throughout normal liver tissue, in association with polycystic kidney disease.-Pathophysiology:Associations with PRKCSH and SEC63 have been described....
  
  
• Pregnancy
  Pregnancy
  Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
  
  
• Premenstrual syndrome
• Weight gain
  Weight gain
  Weight gain is an increase in body weight. This can be either an increase in muscle mass, fat deposits, or excess fluids such as water.-Description:...
  
  
• Ovarian cancer
  Ovarian cancer
  Ovarian cancer is a cancerous growth arising from the ovary. Symptoms are frequently very subtle early on and may include: bloating, pelvic pain, difficulty eating and frequent urination, and are easily confused with other illnesses....
  
  

Treatment

Patients should understand that bloating is not life threatening and there is no need to rush to a physician

Physician

A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...

 every time an episode occurs. In most cases, bloating can be handled with simple home remedies and changes in life style.
However, when bloating has been persistent or recurrent, it is wise to see a physician to ensure that there is no organic cause for the problem. Physicians usually check stools

Human feces

Human feces , also known as a stool, is the waste product of the human digestive system including bacteria. It varies significantly in appearance, according to the state of the digestive system, diet and general health....

 for parasites and other infections.

Foods

Certain foods have been known to worsen bloating. Poorly digested components of many foods are excreted into the large intestine where they are degraded by bacteria, producing excess gas. Depending on the undigested component, this may affect the odor and the volume of gas created.
Excess dietary fiber

Dietary fiber

Dietary fiber, dietary fibre, or sometimes roughage is the indigestible portion of plant foods having two main components:* soluble fiber that is readily fermented in the colon into gases and physiologically active byproducts, and* insoluble fiber that is metabolically inert, absorbing water as it...

 intake is a known cause of belching, gas and bloating. More than 20-25 grs of dietary fiber per day is not recommended.

Many vegetables are known to cause bloating due to high levels of fiber and undigestible sugars such as raffinose

Raffinose

Raffinose is a trisaccharide composed of galactose, fructose, and glucose. It can be found in beans, cabbage, brussels sprouts, broccoli, asparagus, other vegetables, and whole grains. Raffinose can be hydrolyzed to D-galactose and sucrose by the enzyme α-galactosidase , an enzyme not found in the...

 (e.g. beans, cabbage, broccoli) .

There are many individuals who are unable to tolerate dairy products because of lactose intolerance

Lactose intolerance

Lactose intolerance, also called lactase deficiency or hypolactasia, is the inability to digest and metabolize lactose, a sugar found in milk...

. Such foods should be eliminated from diet if symptoms develop.

Medications

For some people, recurrent distension symptoms worsen their quality of life and thus many resort to health supplements or medications.
Beano

Beano (dietary supplement)

Beano is an enzyme-based dietary supplement that is used to reduce gas in the digestive tract, thereby improving digestion and reducing bloating, discomfort, and flatulence caused by gas. It contains the enzyme alpha galactosidase that breaks down oligosaccharides such as raffinose...

 is a formula containing enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

s that help break down complex carbohydrate

Carbohydrate

A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...

s and vegetables. This formula can help reduce gas and belching but often does not reduce bloating.
Other over the counter formulas recommended for bloating include simethicone

Simethicone

Simethicone is an oral anti-foaming agent used to reduce bloating, discomfort and pain caused by excess gas in the stomach or intestinal tract. It is a mixture of polydimethylsiloxane and silica gel.-Chemical action and pharmaceutical effects:...

 and activated charcoal. These are widely used to treat excessive gas and bloating but their efficacy is questionable.
Probiotic

Probiotic

Probiotics are live microorganisms thought to be beneficial to the host organism. According to the currently adopted definition by FAO/WHO, probiotics are: "Live microorganisms which when administered in adequate amounts confer a health benefit on the host"...

s are also used to treat bloating but not everyone responds to these health supplements.
Antidepressant

Antidepressant

An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...

s in low doses have been found to help a few individuals. These agents alter gut perception of fullness and do help relieve anxiety and apprehension.
Alternative health treatments which have been used to treat bloating include acupuncture

Acupuncture

Acupuncture is a type of alternative medicine that treats patients by insertion and manipulation of solid, generally thin needles in the body....

 and hypnosis

Hypnosis

Hypnosis is "a trance state characterized by extreme suggestibility, relaxation and heightened imagination."It is a mental state or imaginative role-enactment . It is usually induced by a procedure known as a hypnotic induction, which is commonly composed of a long series of preliminary...

.

External links

• PediaBook.com at PediaBook.com Encyclopedia
• Overview at University of Maryland Medical Center
  University of Maryland Medical Center
  The University of Maryland Medical Center is a teaching hospital with 705 beds based in Baltimore, Maryland, that provides the full range of health care to people throughout Maryland and the Mid-Atlantic region. It gets more than 35,000 inpatient admissions and 165,000 outpatient visits each year...
  
  
• MedlinePlus/NIH - Abdominal bloating
• MedlinePlus/NIH - Abdomen - swollen