Doxepin therapy for duodenal ulcer: a controlled trial in patients who failed to respond to cimetidine.

Ten patients with endoscopically proven active duodenal ulcers completed a double-blind placebo-controlled trial of doxepin hydrochloride. All ten had previously failed to respond to conventional cimetidine therapy. Doxepin was given at bedtime in a single 50-mg dose for the first week and, if needed, in a single 75-mg or 100-mg dose for the remainder of the six-week trial. After two weeks of therapy the decrease in average ulcer size was 54% in the doxepin group versus 38% in the placebo group (P less than 0.01); at the end of six weeks the decrease in mean ulcer size was 69% in the doxepin group versus 97% in the placebo group, a difference that was not significant. No serious side effects were attributed to doxepin, but two patients complained of mild dryness of the mouth. Suggestions for using this tricyclic antidepressant and possible mechanisms of action are discussed.