Put simply, diarrhoea is when you pass loose, watery stools at a rate that is more frequent than what’s normal for you. It is very common and will affect most people in their lives. Fortunately, in most cases, although unpleasant, it isn’t anything to worry about. The most common cause of diarrhoea in both adults and children is gastroenteritis, which is a viral infection in the bowel.
Faeces can become loose and watery for various reasons. Anxiety, stress or emotional upset can cause the contents of the bowel to move through the digestive system too rapidly. This doesn’t allow the large intestine enough time to absorb the necessary fluid from the stools. A bacterial infection can cause what is known as secretory diarrhoea. This is where too much fluid is secreted into the bowel, diluting the stools consistency. If a virus or bacteria damages the lining of the digestive tract, it can result in the intestines being unable to absorb the fluid content within the bowel, resulting in watery stools.
Medicines can also cause diarrhoea as an unwanted side effect. Antibiotics, antacids, statins and laxatives are all common medicines that can cause diarrhoea. All the causes listed above usually only serve to induce diarrhoea for a short period of time. There are certain conditions that can result in more persistent long-term diarrhoea. These include bowel cancer, chronic pancreatitis, coeliac disease, Crohn’s disease, cystic fibrosis, ulcerative colitis and IBS (irritable bowel syndrome).