A double-blind controlled clinical trial of the new, not yet commercially available drug, carnidazole and tinidazole, was carried out in 77 women with a proven vaginal trichomoniasis. 39 patients and their sexual partners received a single dose of 2 g of carnidazole and the other 38 couples were treated in the same manner with tinidazole. The cure rate was 100% and 95% respectively. The side-effects were higher in the carnidazole group, although they were mild and well-tolerated by the patients and their partners. The history of the disease and its treatment are also briefly reviewed.