Although medication-induced colonotoxicity is uncommon, it is important that it be recognized, because the initial
therapy for this condition is medication discontinuation. This review categorizes the association between the listed medications and colonotoxicity as "well-established" or "probable," according to the following criteria: number of clinical studies by independent clinical investigators, total number of reported cases, plausibility of an association based on experimental and pharmacologic studies, and validity of an association in each reported case. Medications associated with colonic
ischemia include
cocaine,
ergotamine,
estrogen,
amphetamines, digitalis,
methysergide, and
vasopressin. Medications associated with
colonic pseudoobstruction include
narcotics,
phenothiazines,
vincristine,
atropine or other
anticholinergics,
ganglionic blocking agents, and
tricyclic antidepressants. Medications promoting infectious or
necrotizing enterocolitis include numerous
antibiotics associated with
pseudomembranous colitis,
deferoxamine associated with Yersinia
enterocolitis,
chemotherapy associated with neutropenic
colitis, and hyperosmolar medications or formulas in infants. Medications associated with an allergic, inflammatory, or cytotoxic
colitis include
gold compounds, nonsteroidal antiinflammatory drugs,
alpha-methyldopa,
flucytosine,
methotrexate,
salicylates, and
sulfasalazine.
Potassium chloride, administered in slow-release wax matrices, can cause intestinal
ulcers. Chronic
cathartic use leads to colonic hypomotility and abdominal distention.
Methysergide can cause a colonic
stricture due to
retroperitoneal fibrosis. Intrarectally administered compounds that have produced a toxic
colitis include powerful
acids, bases, and other
corrosives.
Enemas using hypertonic radiographic
contrast agents have been associated with
colitis in patients with colonic obstruction.