Abdominal bloating

by Advanced GI WA

What is it?

Abdominal bloating is felt by patients as a feeling of fullness, tightness or distension in the abdomen. Bloating is different to abdominal swelling where the abdomen is actually increased in size but both of these features may be present.

Common causes of abdominal bloating

Abdominal bloating may be a feature of a number of disorders the majority of which are not serious and result from changes in gastrointestinal function. Common causes are listed below:

Diet
Excessive fat or fibre consumption in the diet can cause bloating as the body takes a long time to break down and expel these foods from the body. Other foods can cause bloating due to formation of extra gas these include cabbage, cauliflower, baked beans and salads.
Constipation
This disorder is characterised by a reduction in the frequency of bowel motions and maybe associated with bloating.
Menstruation
Bloating is common in women at the time of menstruation as more or less part of a premenstrual stress disorder.
Irritable bowel syndrome (IBS)
This is a common disorder where patients have abdominal pain classically associated with alternating episodes of constipation and diarrhoea. The pain is frequently eased by passing a bowel motion or passing wind. Abdominal bloating is one of the key features of this condition.
Air swallowing
If you swallow large amounts of air your bowel has trouble absorbing or moving it from the body. This may lead to the sensation of a full bowel. Anxiety or nervousness, eating quickly, gulping food or beverages and chewing gum can all cause you to swallow increasing amounts of air.

Less common causes of abdominal bloating:

Partial bowel obstruction
A blockage at some point in the intestine may lead to bloating and this diagnosis should be suspected if there is a recent onset of nausea and vomiting.
Malabsorption syndromes
A number of disorders exist where the body cannot breakdown and absorb certain components of food. Lactose intolerance, coeliac disease and other food intolerances are examples of conditions that can cause bloating by these mechanisms.
Tumours
Very occasionally you may feel bloated because there is a tumour of the ovary, liver, stomach or elsewhere within the abdomen.
Ascites
A collection of fluid within the abdominal cavity is called ascites. This is also a result of diseases of the liver where it may be associated with malignancy.
Parasitic disorders
If the patient has recently returned from overseas then certain parasitic disorders can cause abnormal dilatations of the colon (megacolon) and lead to bloating.

A detailed history is important particularly such details as the duration of the bloating, the relationship to diet or menstrual cycle. Obviously associated symptoms e.g. nausea, vomiting, constipation and diarrhoea are important. A detailed past medical history e.g. history of malignancy or abdominal surgery and also their current medications e.g. consumption of strong pain killers.

If bloating is of recent onset in someone over the age of 50 then underlying pathology is more likely and screening tests need to be considered:

Blood and stool tests to look for evidence of malabsorption or infection
Plain X rays of the abdomen to look for obstruction
Ultrasound of the abdomen & pelvis to look for ascites and solid organ tumours
Endoscopic investigations may be required if there is a suspicion of intestinal obstruction

Tips for dealing with bloating

Eat slowly and chew food thoroughly
Avoid carbonated beverages and avoid gulping and sipping liquids
Avoid chewing gum and sucking on hard lollies
Eliminate pipes, cigars and cigarette smoking
Eliminate or minimise sugar and artificial sweetener consumption
Cut back on dairy products
Eat small meals, i.e. do not overload the stomach in any one meal
Avoid tight fitting garments
Do not lie down or sit in a slumped position within 2-3 hours after eating
Simethicone and activated charcoal (available over the counter) may provide some benefit
Take a leisurely stroll after meals
Consider peppermint tea

Abdominal bloating associated with recent weight gain

This is a common scenario and unfortunately the only remedy is weight loss!