This is a chronic inflammatory disease that may affect the rectum only (proctitis) or the rectum and a variable length of large intestine or colon (colitis). It may present with profuse watery or bloody diarrhoea and low abdominal pain. It is essential to exclude infection by providing stool specimens at onset of symptoms. Treatment is usually very effective; the route of administration of treatment may depend upon the site of the disease or inflammation. Thus, disease limited to the bottom few centimetres of the bowel (rectum) may be best treated using a suppository whereas more extensive disease may require treatment with tablets by mouth or even foam enemas (inserted into the bottom and squeezed or squirted up into the colon). First line treatment for mild to moderate symptoms is usually with a drug called mesalazine; steroids are reserved for more severe cases or for patients with fail to respond to mesalazines. Some patients require treatment with drugs to suppress the immune system such as mercaptopurine or cyclosporin.