Ulceration of the small intestine due to slow-release potassium chloride tablets.

A retrospective study at surgical clinics in Stockholm County disclosed 22 cases of small-bowel ulceration in which a connection with use of slow-release potassium chloride tablets was probable. Most ulcers had caused stenosis of 1-2 cm of gut, and in four of these cases there was also perforation of the bowel wall. Five patients had perforation without signs of stenosis. The pathology of the ulcers was similar to that described after use of enteric-coated potassium chloride tablets. Since 1970 the frequency of potassium-induced ulceration has been low--3 cases per 100 000 patient-years of slow-release tablet use. On the other hand, this complication of drug therapy can be serious--the mortality in the present series was 27%. Other types of potassium chloride preparations should therefore be tested. Microencapsulated potassium chloride tablets have been reported to be less irritating to the gastrointestinal tract.