Metronidazole-resistant trichomoniasis is an infrequent but challenging problem with no universally successful treatment. Since 1994, we have been using a combination regimen consisting of high-dose tinidazole plus a broad-spectrum antibiotic, i.e. doxycycline or ampicillin, and clotrimazole pessaries, for 7--14 days in this condition. A retrospective case review identified 11 cases of resistant trichomonas between 1994 and 2002. In the absence of resistance testing, resistance was defined clinically. Nine of the 11 patients were cured; one patient did not attend follow-up. In the women who attended for follow-up, the cure rate was 90%. We have found the combination of tinidazole, a broad-spectrum antibiotic, and clotrimazole pessaries to be a tolerable and effective treatment for metronidazole-resistant Trichomonas vaginalis. Although a variety of total doses of tinidazole were used in our patients, based on our findings, and those of others, we would recommend giving tinidazole 2 g twice daily for 14 days (total dose 56 g).