Trichomoniasis is a sexually transmitted infection caused by a parasite. Most men who have it do not have associated symptoms; women with the disease may or may not have symptoms. If present, symptoms in women include gray or yellow-green vaginal discharge and odor. Healthcare providers usually use a single dose of the drug metronidazole to treat the infection.
Trichomoniasis (trick-oh-moe-nye-uh-sis) is one of the most common sexually transmitted infections (STIs). According to the Centers for Disease Control (CDC), an estimated 7.4 million new cases of trichomoniasis occur in men and women every year in the United States.
The disease is caused by a parasite called Trichomonas vaginalis. It is primarily an infection of the urogenital tract. The vagina is the most common place for the infection in women, and the urethra is the most common place in men.
(Click Causes of Trichomoniasis for more information.)
Trichomoniasis, like many other sexually transmitted diseases (STDs), often occurs without any symptoms, especially in men. When women have symptoms, they usually appear within 5 to 28 days after exposure to the parasite.
Although some infected women have minor or no symptoms, many do. Trichomoniasis symptoms in women include:
- Heavy, yellow-green or gray vaginal discharge
- Discomfort during sex
- Vaginal odor
- Painful urination.
They may also have irritation and itching of the genital area and, on rare occasions, lower abdominal pain (stomach pain).
If present, the symptoms in men include a thin, whitish discharge from the penis and painful or difficult urination and ejaculation.