Diarrhoea / Loose Stools

Definition:
The Oxford English Dictionary defines diarrhoea as “a condition of excessively frequent and loose bowel movements”.

As with any symptom you must decide whether to seek medical advice. It is reasonable to ignore the problem or treat yourself if you have mild diarrhoea for a few days. The condition should not make you feel ill, cause undue pain or prolonged vomiting. Fluids and salts lost to the body should be restored with clear soups. Solid foods are unimportant and can be omitted during the episode. Antibiotics are not required for this mild problem. Although it is now possible to obtain powerful anti diarrhoeal medicines without a doctor's prescription it is preferable to get your general practitioner to supervise such medication. Self medication may be needed in a case of travellers diarrhoea.

IT IS NOT SAFE TO TREAT INFANTS AND SMALL CHILDREN IN THIS WAY. Children lose fluids rapidly and may need urgent replacement of these in a hospital.

You should see your doctor:

1. If the initial problem continues or worsens.
2. If there is vomiting which is severe or continues for more than 1 day.
3. If you feel faint or weak.
4. If you are feverish.
5. If there is undue abdominal pain.
6. If there is blood in your motions.
7. If your abdomen has become swollen.
8. If the diarrhoea alternates with constipation.

Causes of diarrhoea:

These are often listed in medical textbooks. The list is extensive and misleading for individual patients. The following list may be more useful:

1. Bowel infections. The common forms of diarrhoea are caused by bacteria or viruses. Stool tests are necessary to identify these. Viruses cannot be treated by antibiotics. To treat such an infection with antibiotics can worsen the problem.
   
   
2. Inflammatory bowel disease. The two major I.B.D.’s are Ulcerative colitis and Crohn’s disease. These are usually diagnosed by looking inside the bowel with a colonoscope and taking a small specimen for analysis. The pictures below show the typical appearance of these.
   
   
   Ulcerative colitis as seen with a colonoscope showing small bleeding ulcers and pus.
   
   
   
   Crohn's disease of the small intestine viewed with a colonoscope.
   
   
3. Incomplete blockage of the bowel. This can cause spurious diarrhoea which usually alternates with constipation. The major diseases which can cause this are pictured below.
   
   
   Cancer of the colon as seen with a colonoscope.
   
   
   
   Diverticulitis as seen with a colonoscope.
   
   
4. Dietetic problems. Specific abnormalities of digestion such as coeliac disease or lactose intolerance may need special diagnostic tests.
   
   
5. Purgative abuse is not uncommon. The picture below shows the abnormal staining of the bowel which can occur.
   
   
   Melanosis coli (Staining of bowel following purgative abuse by the patient.)
   
   
6. Colonic polyps. Certain polyps (villous adenomas) can produce large amounts of fluid resulting in diarrhoea. Multiple polyps can similarly cause diarrhoea.
   
   
   Appearance of a villous adenoma of the colon as seen with a colonoscope.
   
   
   
   Multiple polyps as seen with a colonoscope.
   
   
7. Overuse of antibiotics can result in diarrhoea.
   
   
8. Irradiation for prostate and other cancers can damage the bowel causing the condition.
   
   
9. Irritable bowel syndrome also called spastic colon can cause diarrhoea. Colonoscopy does not show any abnormality with this condition.
   
   
10. There are other causes of diarrhoea which are not mentioned in this pamphlet. Your doctor will advise you about these if necessary.

Treatment

No one treatment can be contemplated for such a complex variety of conditions. Your doctor will give you the best advice.

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