What is Diarrhoea?

Diarrhoea is characterised by passage of loose or watery stools three or more times in a day. Diarrhoea is often defined as passing of increased amounts (more than 300g in 24 hours) of loose stools in a day.

Types of diarrhoea: There are three types of diarrhoea:

• Acute diarrhoea,
• Persistent diarrhoea, and
• Dysentery.

Acute diarrhoea: When an episode of diarrhoea lasts less than 14 days, it is known as acute diarrhoea. Acute watery diarrhoea can cause dehydration (loss of electrolyte and water) and contribute to malnutrition. Acute diarrhoea is leading cause of children’s death in developing countries. Death in acute diarrhoea is most often caused by dehydration.

Chronic diarrhoea: If the diarrhoea lasts for 14 days or more, it is known as chronic or persistent diarrhoea. An acute episode of diarrhoea may become chronic in about 20% of cases. Persistent diarrhoea increases the risk of malnutrition and may cause dehydration.

Dysentery: If there is blood in the stool during diarrhoea – with or without mucus – it is called dysentery. Dysentery is a serious kind of diarrhoea as it can lead to anorexia, rapid weight loss, and damage to the intestinal mucosa, and other complications such as sepsis.

What causes diarrhoea?

Acute diarrhoea is most often caused by an infection with virus or bacteria. Other causes of acute diarrhoea include food poisoning and side effect of  antibiotics. Infection usually occurs after consumption of contaminated drinking water or food. It is not possible to assess the quality of food or water for contamination with  germs by its smell or the way it looks. Most contaminated food and water usually looks and tastes all right.

Chronic diarrhoea may be caused by infection or it may be a symptom of some other disorder. Some disorders which may cause chronic diarrhoea include:

• Irritable bowel syndrome.
• Intestinal infections (acute, recurrent or chronic).
• Chronic intestinal inflammation (ulcerative colitis and Crohn's disease).
• Chronic pancreatitis.
• Laxatives.
• Lactose intolerance.
• Improper diet (consumption of too much alcohol, coffee or sweets).
• Metabolic disorders such as diabetes and thyrotoxicosis.
• Allergy to gluten (wheat protein).

Common symptoms of diarrhoea include frequent watery stool which may be accompanied by cramping, abdominal pain, nausea and vomiting. Some people may have an urgent need to use the bathroom, or may have loss of bowel control (more common in children). Repeated diarrhoea and vomiting can cause dehydration (loss of electrolytes and water from the body).

Antibiotics are not needed in most people with diarrhoea. Most cases of acute diarrhoea can be treated at home with fluids, preferably containing sugar and salts. Ready-mixed rehydration sachets added to drinking water is preferable to plain water. People with severe dehydration may have to be hospitalised for fluid replacement. Drinking plenty of water and oral rehydration solution can help to prevent dehydration.