In diagnosing trichomoniasis, a physician will compile a medical history and perform a complete physical examination, including a pelvic examination. During a pelvic examination, the physician will open the walls of the vagina and look for small red sores inside the vagina or on the cervix.

A sample of vaginal fluid will be obtained and examined under a microscope to determine the presence of parasites. Additional tests that may be performed include a vaginal culture or DNA test. Physicians frequently test for STDs (sexually transmitted diseases), such as gonorrhea and chlamydia, which often can accompany trichomoniasis.

In most cases, trichomoniasis is treated with a single oral dose of 2 grams of the prescription drug metronidazole. 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, for treatment of trichomoniasis. This drug is now being used in patients who fail to respond to treatment with metronidazole.

Unlike some STDs, 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 and a topical medicine called paromomycin may be prescribed.

The U.S. Centers for Disease Control and Prevention (CDC) 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 also should refrain from sexual relations until they and their partners have completed treatment and are no longer exhibiting symptoms.

Women should not take these medications for this condition during the first three months of pregnancy, according to the FDA. However, after the first trimester, metronidazole or tinidazole may be taken if necessary. The National Women’s Health Information Center suggests treating pregnant women who have symptoms and not treating those who have no symptoms.

Individuals who are successfully treated for trichomoniasis can still become infected again in the future if they are exposed to the parasite.