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Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention


Trichomoniasis is a common sexually transmitted disease (STD). It often affects the lower genital tract in women and inside of the penis in men.


Trichomoniasis is caused by a specific parasite. The parasite is passed through sexual contact. It mainly affects genital tissue.

Risk Factors

Factors that may increase your chance of trichomoniasis include:

  • Multiple sexual partners
  • Sex without a condom
  • History of STDs


Trichomoniasis does not always cause symptoms. Men are less likely to have symptoms than women.

Symptoms in women may include:

  • A foul-smelling, greenish-yellow or gray discharge from the vagina—often in large amounts
  • Irritation, itching, and/or soreness in the genitals
  • Pain or discomfort when urinating
  • Pain or discomfort with sex

Infection Site in Women


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Symptoms in men may include:

  • Discharge from the penis
  • Itching and/or irritation in the urethra
  • Pain or discomfort when urinating
  • Burning sensation after ejaculation

Infection Site in Men

Male Urethtra

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You will be asked about your symptoms and medical history. A physical exam will be done. Vaginal fluid or discharge will be examined from women. Urine, semen, or penile discharge will be examined from men. The samples can be sent to a lab to confirm trichomoniasis.


Trichomoniasis is can be treated with antibiotics. The antibiotic may be given in a single dose or a weeklong course.

Trichomoniasis is easily passed back and forth between sexual partners. Your partner(s) should also be treated, even if symptoms are not present. An infected person can infect their sexual partners even if they do not have symptoms.

Avoid sex until your treatment is done and your symptoms are gone.


To help prevent sexually transmitted diseases (STDs) like trichomoniasis:

  • Always use condoms during sexual intercourse.
  • Have a mutually monogamous relationship. This means 1 sex partner.




  • Trichomoniasis. Centers for Disease Control and Prevention website. Available at: Updated April 28, 2015. Accessed May 28, 2015.
  • Trichomoniasis. EBSCO DynaMed website. Available at: Updated March 17, 2015. Accessed May 28, 2015.
  • Trichomoniasis. National Institute of Allergy and Infectious Diseases website. Available at: Updated February 28, 2013. Accessed May 28, 2015.
  • Workowski KA, Berman S, Centers for Disease Control and Prevention. Sexually Transmitted Diseases Treatment Guidelines, 2010. MMWR 2010;59(No. RR-12):1-110.

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