Trichomoniasis (trik-oh-mown-eye-a-sis) is a curable sexually transmitted infection (STI) caused by a parasite. Infection is more common in people with a vagina than in people with a penis. Having trichomoniasis increases the risk of catching or spreading other STIs.


Symptoms can vary.

  • Itching or irritation inside the penis
  • Burning after urination or ejaculation
  • Discharge from the penis
  • Discomfort/pain during sexual intercourse
  • Itching or irritation around the vagina
  • Burning after urination
  • A watery yellowish or greenish bubbly vaginal discharge
  • Discomfort/pain during sexual intercourse


Trichomoniasis can be diagnosed only through laboratory testing. It is treated with oral antibiotics. It is also necessary to treat the sexual partner(s) of infected individuals and to wait 7–10 days after completion of the treatment to engage in sexual intercourse.

When to Seek Medical Attention

If you experience any of the above symptoms, consult with your healthcare provider.

Causes & Prevention

Trichomoniasis passes from person to person during vaginal, oral, and anal sex, or other forms of sexual contact. Penetration and/or ejaculation do not need to occur to spread the infection. The parasite can also be passed between women.

As with all STIs, the only way to avoid all risk of infection if to abstain from sex (vaginal, anal, and oral) and intimate skin-to-skin contact.

If you are sexually active:

  • Use condoms and/or dental dams consistently every time you have sex (anal, oral, or vaginal)
  • Communicate with your partner(s) about STIs, testing and using condoms and/or dental dams.
  • If using sex toys, follow the instructions on how to clean them properly after each use. If they have no batteries/electrical wires, wash with soap and water and allow to dry.
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