DIARRHOEA

What is it?

Diarrhoea means there are frequent, loose or liquid stools. There may be a gripey abdominal pain (colic) which is less after a stool is passed.

Acute diarrhoea - comes on suddenly and lasts a short time.

Chronic diarrhoea - affects someone over a long period of time. Some people pass frequent, small solid stools with a sense of urgency. This is not true diarrhoea and occurs when the rectum is irritable as in the irritable bowel syndrome or inflamed as in colitis.

Who gets it?

Too much fluid is passed (secreted) from the blood-stream into the bowel, for example in gastroenteritis. This is how some laxatives work. The bowel moves its contents through too quickly and too little fluid is passed back into the bloodstream. This is one way in which anxiety produces diarrhoea. More liquid is drunk than the bowel can cope with - this seldom happens, but is one way in which drinking too much beer can cause diarrhoea.

Acute diarrhoea - Food poisoning. Gastroenteritis (see separate leaflet on the prevention and treatment of travellers’ diarrhoea). Anxiety. Sometimes treatment with an antibiotic. Alcohol (to excess).

Chronic diarrhoea - When diarrhoea goes on for a long time, the most likely cause is the irritable bowel syndrome. It is called a ‘functional’ condition. This means that the bowel produces stools which are looser or more frequent than normal, although the bowel is not diseased.

Less commonly, there are also several conditions which cause chronic diarrhoea:

• inflammation of the bowel - eg. ulcerative colitis or Crohn’s disease. The diarrhoea in ulcerative colitis often contains blood
• poor absorption of food - eg. coeliac disease or chronic disease of the pancreas, when the stools may be very pale, offensive smelling and difficult to flush away
• hormonal changes - eg. diabetes or an overactive thyroid gland
• some bowel cancers
• chronic bowel infections
• some stomach operations
• some drugs including antibiotics, magnesium-containing antacids, pills for blood pressure or arthritis and laxatives
• foods including milk in some people who digest milk sugar (lactose) poorly and wheat products in patients with coeliac disease and consumption of unusually large amounts of alcohol. True food allergy is very rare.

When should I go to my GP?

After a few days if acute diarrhoea does not settle.

Earlier for:
- severe diarrhoea with dehydration
- the elderly and the very young (under 2 years).

You should ask for an early appointment with the doctor if liquid stools contain blood and/or if you are losing weight.

What tests will the Doctor want to do?

• After listening to you and doing a general examination, the doctor will usually examine the rectum (back passage) with a finger. The doctor may:
• pass an instrument through the back passage to examine the lining of the bowel arrange laboratory examination of stool samples to see if there is infection
• arrange blood tests
• arrange a barium X-Ray examination of your bowel. (A barium enema involves the insertion into the rectum of a harmless material which shows up on an X-ray, allowing the doctor to see any abnormalities)
• arrange a flexible sigmoidoscopy or colonoscopy (inserting a flexible telescope into the back passage so the doctor can see the whole or part of the colon).

What is the treatment?

Acute Diarrhoea -(usually improves within a few days).
Ask yourself whether this is due to anxiety, medicines or alcohol.
Keep up a good fluid intake, using rehydration solutions when much liquid is passed to replace lost fluid and salt.
Observe good hygiene, in case the diarrhoea is infectious.
Wash your hands thoroughly after going to the toilet.
Don’t prepare food for other people, especially babies and old people.
Consider taking an anti-diarrhoeal drug such as loperamide or diphenoxylate which can be obtained for adults without a prescription if the symptoms are severe, but always read the label and ask your pharmacist for advice if unsure.
IT IS DANGEROUS TO GIVE THESE TO BABIES AND CHILDREN WITHOUT MEDICAL ADVICE.
The doctor may prescribe an antibiotic if a severe infection is diagnosed or suspected.

Chronic Diarrhoea -(continuing for weeks or months)
Do not treat yourself without seeing a doctor. There may be an underlying disease which can be cured. In most cases, chronic diarrhoea is not serious and can be controlled by medicines, but this is best done under medical supervision.