title: Optimal dosing of trimethoprim-sulfamethoxazole when used with loperamide to treat traveler's diarrhea.
abstract: To explore the optimal dosing regimen for trimethoprim-sulfamethoxazole (TMP-SMX) when used in combination with loperamide to treat traveler's diarrhea, 190 U.S. adults with acute diarrhea were enrolled in a double-blind, randomized trial in Guadalajara, Mexico. All patients received loperamide (4-mg loading dose; 2 mg after each loose stool, not to exceed 16 mg/day for 3 days) and were randomized to receive a 3-day course of TMP-SMX (160:800 mg twice daily for six doses) (group A), a single large dose of TMP-SMX (320:1,600 mg) (group B), or a large loading dose (320:1,600 mg) followed by standard doses for 3 days (160:800 mg twice daily for five doses) (group C). Patients in group C responded best (P < 0.01), with 75% of subjects recovered from diarrhea in 12 h compared with 34 h (group A) and 33 h (group B). Similar differences in favor of group C were noted in the subset of patients who presented with moderate to severe diarrhea. On average, patients in group C took significantly (P < 0.05) less loperamide (1.2 mg) after the 4-mg loading dose compared with patients in group A (2.4 mg) or group B (2.0 mg). We conclude that the most efficacious treatment of traveler's diarrhea in the interior of Mexico is to take loperamide in usual doses to control symptoms in combination with a single large dose of TMP-SMX, which should then be continued for 3 days in standard doses.
authors: Center for Infectious Diseases, University of Texas Medical School/School of Public Health, Houston 77030.
authors: C D
authors: CD
authors: Ericsson
authors: I
authors: I
authors: Nicholls-Vasquez
authors: H L
authors: HL
authors: DuPont
authors: J J
authors: JJ
authors: Mathewson
mesh_terms: D000208:Acute Disease; D000328:Adult; D003967:Diarrhea / Q000188:drug therapy* / Q000382:microbiology; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004347:Drug Interactions; D005260:Female; D006801:Humans; D008139:Loperamide / Q000627:therapeutic use*; D008297:Male; D011446:Prospective Studies; D014195:Travel; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D008139:Loperamide; D015662:Trimethoprim, Sulfamethoxazole Drug Combination