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What is trichomoniasis?

Trichomoniasis is an infection of the vagina and penis. It is a sexually transmitted disease that can be treated and does not cause any serious permanent damage. However, if a pregnant woman is infected and does not get treated, the disease can cause the baby to be born early or have a low birth weight (less than 5 pounds).

How does it occur?

A tiny organism called Trichomonas vaginalis causes the infection. Sexual partners not using condoms can spread these organisms to each other during sex.

What are the symptoms?

Many women who have trichomoniasis do not have any symptoms. When they do have symptoms, the most common ones are:

  • frothy, green or yellow vaginal discharge with strong odor
  • itching, redness, and soreness of the vagina
  • burning when going to the bathroom
  • pain in the vagina during sex.

Men usually do not have symptoms. Some men may temporarily have an irritation inside the penis, mild discharge, or slight burning after urination or ejaculation.

How is it diagnosed?

Your health care provider will examine you. Your provider will get a sample of fluid from the vagina or penis and look for trichomonas under the microscope.

Your health care provider may also test for other sexually transmitted infections.

How is it treated?

Trichomoniasis is treated with a medicine called metronidazole, or Flagyl.

Do not drink any alcohol while you are taking Flagyl and for 2 days after you finish the medication. Drinking alcohol while you are taking Flagyl may cause a severe nausea and vomiting.

Flagyl may be taken with food to prevent nausea and vomiting (possible side effects of the drug).

Your sexual partner also needs to be treated at the same time.

How long will the effects last?

For most people, the symptoms disappear less than 1 week after treatment.

The symptoms of trichomoniasis in infected men may go away in a few weeks without treatment. However, an infected man, even one who has no symptoms, can keep infecting or reinfecting a female partner until he has been treated.

The genital inflammation caused by trichomoniasis can make it easier for a woman to become infected with HIV if she is exposed to the HIV virus. Having trichomoniasis may increase the chance that an HIV-infected woman passes HIV to sex partners.

How can I take care of myself?

  • If you may be or are pregnant, tell your health care provider.
  • Tell everyone with whom you have had sex in the last 3 months about your infection. They must also be treated with Flagyl, even if they have no symptoms. Do not have sex until your symptoms are gone and both you and your partner have finished your treatment.
  • Follow your provider's instructions for follow-up visits and tests.

Call your health care provider if:

  • Your symptoms last more than 7 days.
  • You have other questions or concerns.

How can I help prevent trichomoniasis?

  • Make sure you tell anyone with whom you have had sex that they have been exposed to trichomoniasis.
  • Reduce the risk of infection by always using latex or polyurethane condoms during foreplay and sexual intercourse.
  • Have just 1 sexual partner who is not sexually active with anyone else. Make sure your partner has been tested for trichomoniasis and other sexually transmitted diseases.
  • Even if you don't have symptoms but have had unprotected sex (without a condom), see your health care provider to be checked for sexually transmitted diseases. If you have been sexually assaulted and are at risk for having been infected, you should be treated.
Developed by David W. Kaplan, MD, and McKesson Provider Technologies.
Published by McKesson Provider Technologies.
Last modified: 2006-03-30
Last reviewed: 2006-01-03
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.
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