In most cases, trichomoniasis is treated with a single oral dose of the prescription drug metronidazole which is used to treat bacterial, fungal and parasitic infections.   If this fails to cure the infection, a longer treatment regimen of three to five days may be required.

In 2004, the U.S. Food and Drug Administration (FDA) approved another drug, tinidazole, to treat trichomoniasis and other protozoa infections. This drug is now being used in patients who fail to respond to treatment with metronidazole.

Unlike some sexually transmitted diseases, trichomoniasis has not developed strains that are resistant to medications, so the prognosis for patients who take these medications is excellent. In about 5 percent of cases, women do not respond to standard treatments. In such situations, an allergy to the medication may be to blame for the lack of success.

Patients who are allergic to metronidazole or tinidazole may receive a prescription for a topical medication called paromomycin. While topical medications may reduce symptoms, they usually are less effective than metronidazole or tinidazole and may not cure the infection. 

The U.S. Centers for Disease Control and Prevention recommends that both partners receive treatment if one partner has been diagnosed with trichomoniasis. This will ensure that any traces of the parasite in either partner are eliminated and will not be further transmitted. Patients should refrain from sexual activity while they are being treated or until their symptoms subside.