What is trichomonas?

Trichomonas (commonly known as ‘trike') is a sexually transmitted infection (STI) caused by a parasite. It can cause infection of the vagina or cervix (neck of the womb) in women and the urethra (urine passage) in both women and men. Trichomonas is one of the most common STIs in some parts of the world but it is not as common in Australia.

How do you get trichomonas?

Trichomonas is passed on through unprotected vaginal sex with someone who already has the infection. Trichomonas can be transmitted by having unprotected sexual intercourse with an infected person. The parasites can live for a few hours on damp towels, so can be spread by sharing towels.

Trichomonas cannot be spread by contact with toilet seats.

How can I protect myself from trichomonas?

The best way to prevent getting trichomonas and other STIs is to have safe sex. This means using a condom every time you have sex.

  • Use a condom when you have vaginal, oral or anal sex.

What are the symptoms of trichomonas?

Up to 50% of women with trichomonas have no symptoms.

Men usually have no symptoms. If you do get symptoms, they usually appear 4-20 days after you get the infection.

Symptoms are different for men and women.

For women, symptoms may include:

  • frothy yellow or green vaginal discharge
  • fishy vaginal smell
  • bleeding after sex or in between periods
  • burning or pain when passing urine or during sex
  • vaginal burning

For men, symptoms may include:

  • burning or pain when passing urine
  • discharge from the opening of the penis

Even when you have no symptoms, you can still have the infection and pass it on to your partners.

How do I get tested for trichomonas?

Women can be tested by taking a urine sample or by taking a swab from the vagina. Men can be tested for trichomonas by taking a urine sample.

How is trichomonas treated?

Antibiotics are used to treat infection with trichomonas. You will be advised to have no sex at all, even with a condom, until 7 days after you have started your antibiotics. It is important that you take the antibiotics as directed by your doctor. Your partner needs to be treated too.

What is contact tracing?

Your doctor will explain who needs to be contacted and treated if you have a trichomonas infection and can also help you with contact tracing. If you have trichomonas and have unprotected sex it is likely that you will pass the infection on to your partner. It is important to let your sexual partners know if you have trichomonas so that they can also get tested and treated. Contact tracing can be done confidentially. There are websites that let you send a free anonymous text message or email – just ask your doctor or nurse about it.

What about pregnancy and trichomonas?

If you are pregnant, trichomonas may cause your baby to be born early or to be underweight. The infection can be safely treated in pregnancy. The infection is rarely passed on from mother to baby during birth.

For more information

Family Planning NSW or 1300 658 886
National Relay Service (for deaf people) – 13 36 77
TIS National's immediate interpreting service131 450
Visit your nearest Family Planning NSW clinic –
NSW Sexual Health or 1800 451 624
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