Treatment of trichomoniasis infection with metronidazole usually takes about 1 week to kill the trichomonas. Trichomonas vaginalis infection can cause trichomoniasis, which is a common gynecological infection. The main manifestations are itching of the vulva, increased vaginal discharge that is thin, purulent and foamy, and congestion and edema of the vaginal wall. Generally, trichomoniasis can be treated with metronidazole, tinidazole and ornidazole for about 1 week to kill the trichomonads and to relieve the symptoms or even to cure them. The systemic medication with local treatment is more effective. It is important to note that trichomoniasis is a sexually transmitted disease, and couples need to be treated together and avoid sexual intercourse or take necessary protective measures during treatment. In addition, trichomoniasis is prone to recur after menstruation. It is recommended to review the treatment for 3 months and repeat the treatment with metronidazole if recurrence is detected.