Trichomoniasis

Trichomoniasis is a sexually transmitted infection (STI) caused by a parasite called Trichomonas vaginalis.
Trichomoniasis can infect the penis, vagina, cervix (Opens in new tab) or urethra (tube that urine passes through).
In Australia, trichomoniasis is more common among:
Trichomoniasis can affect females and males.
Symptoms of trichomoniasis usually start 4 to 20 days after you have been infected and can include:
Some people do not have any symptoms, especially males. You can still pass the infection to partners even if you do not have symptoms.
Trichomoniasis is caused by a parasite called Trichomonas vaginalis.
You should see your doctor, visit a family planning clinic (Opens in new tab) or a sexual health clinic if you:
You can catch trichomoniasis during unprotected vaginal sex with an infected partner.
Anyone who is sexually active can catch it and pass it on.
Trichomoniasis can also be spread by sharing wet towels with someone who is infected as the parasite can live on wet towels for a few hours.
You cannot catch trichomoniasis from contact with toilet seats.
Your doctor can diagnose trichomoniasis by sending a swab of vaginal discharge or a urine (wee) sample to a laboratory.
Your doctor may recommend testing for other sexually transmitted infections (STIs) at the same time.
Trichomoniasis is treated with an antibiotic medicine called metronidazole. Your doctor may prescribe a single large dose or a longer course lasting 7 days.
You should take metronidazole with food. Avoid alcohol during your treatment and for 24 to 48 hours after you finish taking antibiotics.
You should tell all your current and recent sexual partners so they can be tested and treated, even if they do not have any symptoms.
You should avoid sexual contact, even with a condom, for 7 days after you start treatment, or until you finish the antibiotics and your symptoms have gone away — whichever is later.
If your symptoms do not resolve after treatment, speak with your doctor or sexual health clinic.
If you have trichomoniasis, you should tell all your sexual partners. That way they can also get tested and treated if needed. This helps to stop the infection from spreading. Your doctor can help you decide who needs to be told.
If you are worried about telling recent sexual partners that you have trichomoniasis, you can send them an anonymous text message or email through some websites, such as Let Them Know (Opens in new tab).
Trichomoniasis is only a notifiable condition in the Northern Territory.
Untreated trichomoniasis stays in your system for months or years. You are also at a higher risk of getting HIV if you have trichomoniasis.
If you are pregnant, trichomoniasis can increase your chance of labour early (Opens in new tab) or your baby being born with a low birth weight (Opens in new tab).
The best way to prevent getting trichomoniasis is to have safe sex. Use a condom every time you have vaginal, anal or oral sex. Safe sex will also protect you from most other STIs.
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Last reviewed: December 2025





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