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Diarrhoea (adults)

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Diarrhoea (adults)


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Diarrhoea describes uncontrollable bowel movements that produce loose, watery stools. These bowel movements tend to be very frequent, occur randomly and are often accompanied by stomach ache and vomiting. Although diarrhoea is a common problem which often gets better by itself, sufferers should be careful they do not dehydrate, as large amounts of water can be lost during a bout of diarrhoea. The very young and the elderly are most vulnerable to dehydration. Severe dehydration requires urgent hospital treatment.
Diarrhoea is caused by an irritation of the intestine (gastroenteritis). The irritation increases contractions of the bowel, producing the spasms and giving less time for water to be absorbed from the intestines. Water and salts are also secreted into the bowel, adding to the watery consistency of the stools.

The most common triggers for diarrhoea are viral (eg rotavirus, norovirus) and bacterial (eg Shigella, Campylobacter) infections. Food contamination, due to undercooked or poorly stored food is a major culprit in introducing these germs into the gut. Water, if it has not been filtered or treated, can also carry germs that cause diarrhoea. Not washing hands after going to the toilet can also pass diarrhoea-causing bacteria from one person to another, a major problem with the spread of a bacterium called Clostridium difficile in hospitals. Other causes of diarrhoea include parasites such as Giardia, stress, spicy foods, too much alcohol and certain prescribed medicines such as antibiotics.

If diarrhoea persists for more than two weeks it is said to be chronic. In this case, the chronic diarrhoea is usually a symptom of some other long term illness such as ulcerative colitis, Crohn's disease or irritable bowel syndrome. Sensitivity to gluten or lactose can also be a cause of chronic diarrhoea.
Extremely loose and watery stools, passed at frequent intervals throughout the day or night. Bowel movements may be uncontrollable. Stomach pain, nausea and vomiting may also accompany diarrhoea. Headache and tiredness may also be experienced if there is dehydration. If there is an infection, the person may also have a fever.
Drink plenty of water and take a rehydration supplement to replace lost fluids, salts and sugars. If you feel like it, eat small amounts of plain foods such as boiled rice or dry toast. Avoid dairy products and fresh foods as these may increase the urge to move the bowel. Bulk forming products such as ispaghula and methylcellulose help absorbs water in the gut and so make stools less loose. They are particularly useful in diarrhoea associated with diverticular disease. Anti-diarrhoeal treatments containing morphine, codeine or loperamide, reduce the spasm of the gut and help stem the flow of diarrhoea. If diarrhoea is accompanied by fever or if an infection is suspected, anti-diarrhoeal medicines should not be used and medical advice should be obtained.

Antibiotics are usually unnecessary because most cases of infective diarrhoea that occur in the United Kingdom are caused by a virus, but if travelling abroad, ciprofloxacin may be used occasionally for the prevention of diarrhoea. Diarrhoea while travelling abroad or after recently returning from abroad may be a sign of a systemic or parasitic infection and may require antibiotic treatment.
When to consult your pharmacist
Your pharmacy stocks a wide range of rehydration supplements and anti-diarrhoeal medicines that can be purchased without a prescription. When purchasing these items always describe your symptoms to your pharmacist and let him or her know as much information about the person with diarrhoea, in particular how old they are, if they are pregnant, have any other illnesses or are taking any other medicines.
When to consult your doctor
Seek medical advice if diarrhoea persists for more than a few days, if blood is found in the stools, if there is a fever, if the bouts of diarrhoea are particularly powerful or continuous. Your doctor will examine you to determine if the diarrhoea is a symptom of another illness and may want to send you to hospital for further tests. You should also visit your doctor if you have recently returned from a holiday abroad and your diarrhoea has got worse. Your doctor may ask for a sample of your stools to test for the presence of bacteria or parasites. If diarrhoea is a side effect of prescribed medicines, your doctor may decide to change your medication.
Useful Tips
  • Adopt good food hygiene in the kitchen - minimise the spread of bacteria by covering foods kept in the fridge and cleaning work surfaces thoroughly
  • Avoid foods that you know irritate you, such as spicy foods or dairy products
  • Wash hands before handling food - this reduces the chance of any germs passing from your hands to the food
  • Take care when drinking water abroad - stick to bottled water and avoid salads that may have been washed with contaminated water - avoid ice in drinks!