INTRODUCTION: The use of retrograde irrigation enemas is common in the treatment of chronic constipation, especially in the elderly. Perforation of the rectum and sigmoid colon caused by cleansing enemas, used by chronically constipated patients, has not been previously described. METHODS: We reviewed all patients with colorectal perforations caused by irrigation enemas admitted to our service in the three-year period between January 1995 and December 1997. RESULTS: Thirteen patients were treated by our surgical service because of perforations of the rectum and sigmoid colon related to a previous retrograde irrigation enema. Ten of these patients came from nursing homes, and the other three lived at home. The relevant information relating the enema administration to the patient's condition was given in only two of the ten patients referred to the emergency room by the institution's nursing or medical staff. In the other eight the information was vague and sometimes misleading. The diagnosis of colorectal perforation was made by history, plain abdominal x-rays, and CT scan with or without meglumine diatrizoate enemas. Ten patients survived, regardless of age, previous diseases, or operative findings. In all of them, diagnosis was made within 36 hours from the perforation. The three deaths occurred in patients in whom the diagnosis was made late. CONCLUSIONS: Awareness of the possible injury from enemas administered to chronically constipated patients should be stressed. A high degree of suspicion by the attending physician is extremely important, because prompt diagnosis and early surgical treatment carries a relatively good prognosis.