piperidines and bismuth-subsalicylate

An open-label, parallel comparison of loperamide hydrochloride (Imodium A-D) and bismuth subsalicylate (Pepto-Bismol) was conducted using nonprescription dosages in adult students with acute diarrhea (three or more unformed stools in the preceding 24 hours plus at least one additional symptom of enteric infection). For the two-day study period, the daily dosage was limited to 8 mg (40 ml) for loperamide-treated subjects and to 4.9 g for bismuth subsalicylate-treated subjects. At these dosages, loperamide significantly reduced the average number of unformed bowel movements relative to bismuth subsalicylate. Following the initial dose of treatment, control of diarrhea was maintained significantly longer with loperamide than with bismuth subsalicylate. Time to last unformed stool was significantly shorter with loperamide than with bismuth subsalicylate. In providing overall subjective relief, subjects rated loperamide significantly better than bismuth subsalicylate at the end of the 24 hours. Both treatments were well tolerated, and none of the minor adverse effects reported resulted in discontinuation of therapy. It was concluded that loperamide is effective at a daily dosage limit of 8 mg (40 ml) for the treatment of acute nonspecific diarrhea and provides faster, more effective relief than bismuth subsalicylate.

Topics: Acute Disease; Adult; Bismuth; Clinical Trials as Topic; Diarrhea; Dose-Response Relationship, Drug; Female; Humans; Loperamide; Male; Nonprescription Drugs; Organometallic Compounds; Piperidines; Salicylates

Loperamide hydrochloride was compared with bismuth subsalicylate for the treatment of acute nondysenteric travelers' diarrhea in 219 students visiting seven countries in Latin America. Subjects whose condition was not improved with therapy could elect to take trimethoprim-sulfamethoxazole. Persons receiving loperamide passed fewer unformed stools when compared with the bismuth subsalicylate group during the first four hours of therapy, from four to 24 hours, and from 24 to 48 hours after therapy was initiated. Among subjects with disease due to enterotoxigenic Escherichia coli, Shigella sp, other pathogens, and unknown agents, fewer unformed stools were passed by the loperamide-treated subjects than the bismuth subsalicylate-treated subjects for all time periods studied. No significant prolongation of disease was seen in subjects with shigellosis treated with loperamide. Eight of the loperamide-treated subjects experienced constipation compared with one in the bismuth subsalicylate-treated group; otherwise, there was no difference in minor side effects experienced between both treatment groups. We conclude that loperamide is a safe and effective alternative to bismuth subsalicylate for the treatment of nondysenteric travelers' diarrhea.

Topics: Acute Disease; Adult; Antidiarrheals; Bismuth; Diarrhea; Humans; Latin America; Loperamide; Organometallic Compounds; Piperidines; Salicylates; Travel; United States