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Trichomonas Infection

Trichomonas Infection, also known as ‘TV’ or ‘Trichs’, is a sexually transmitted infection (STI) caused by a small parasite.

It infects the genitals of both men and women, and may also lead to infection in the urethra (the passage carrying urine from the bladder) and prostate gland (in men).

How it's caught

Trichomonas infection spreads through unprotected sex and sharing sex toys.

Because many people have no symptoms and do not know they have a trichomonas infection, you or your partner could have picked up the infection from a previous partner without even knowing it.


Trichomonas causes genital itching and soreness, and can lead to infections of the urethra (the passage that carries pee from the bladder) and, in men, infection of the prostate gland.

Almost half of all people with trichomonas infection will have no symptoms.

If symptoms are present, these usually include a yellow or green discharge from the penis or vagina, which can sometimes have an unpleasant, ‘fishy’ smell.

You may have pain or a burning sensation when peeing, or itching and soreness in the genital area.

Women may also experience pain or discomfort during sex.

If you think you or your partner may have a trichomonas infection, it's important to get tested.


Testing for trichomonas infection is quick and straightforward but if you or your partner are worried that you may have it, see a doctor straight away. You can visit your local GP surgery, or a sexual health service.

You may be asked to provide a urine sample, or the nurse or doctor may use a swab to collect a sample of discharge from the vagina or penis. A swab looks a bit like a cotton bud, and collecting a sample only takes a few seconds and is not painful, although it may be a little uncomfortable for a moment. Most sexual health clinics can look at the sample straightaway under the microscope and see the parasite. In some, and at your GP, the swab needs to be sent away to the laboratory to make the diagnosis.


Trichomonas infection can be effectively treated with antibiotics.

Your partner should also be treated, and you may both usually be asked to return to the clinic for another test a week or so later to check that the infection has been successfully treated.


The best way to prevent all sexually transmitted infections is to practice safer sex. This means using a condom for vaginal or anal sex, a dam or condom for oral sex or practicing safer sex alternatives.

If you have been diagnosed with Trichomonas infection, it is important to avoid having sex until you and your partner have both finished treatment, otherwise you could be re-infected.


For more information call  0800 22 44 88 or use our sexual health service finder to look for help in your area.