Trichomoniasis

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Overview

Trichomoniasis is a sexually transmitted infection (STI) caused by a tiny parasite called Trichomonas vaginalis (TV).

Symptoms of trichomoniasis

Symptoms of trichomoniasis usually develop within a month of infection.

But up to half of all people will not develop any symptoms (though they can still pass the infection on to others).

The symptoms of trichomoniasis are similar to those of many other sexually transmitted infections (STIs), so it can sometimes be difficult to diagnose.

Symptoms in women

Women may not notice anything wrong but they can still pass on TV to their sexual partner. Some women may notice one or more of the following: ·

  • increased vaginal discharge
  • an unpleasant vaginal smell
  • ‘cystitis’ or burning pain when passing urine
  • vulval itching or soreness · pain in the vagina during sex

Symptoms in men

Most men will not feel anything wrong but they can still pass TV on to their sexual partner. Some men may notice one or more of the following:

  • a discharge from the tip of the penis
  • a burning pain when they pass urine
  • they want to pass urine more often than normal
  • soreness around the foreskin

When to seek medical advice

See a GP or go to your local sexual health clinic if you develop any of the symptoms of trichomoniasis or you think you may be infected.

How do I get tested for TV?

 In women:

  • It is not a routine test in all clinics, but is usually done if you have symptoms. If you do have symptoms, it is best if a swab is taken from the upper vagina by a doctor or nurse during an internal examination. Some clinics can test for TV on a urine sample. If this test is planned you should not have passed urine for an hour.

In men:

  • In most clinics it is not routine for men to be tested for TV. Men usually have a TV test because their sexual partner has tested positive. A swab is taken from the tip of the penis. Some clinics can test for TV on a urine sample. If this test is planned you should not have passed urine for an hour.

Most of the tests for TV do not work very well in men and this explains why most men with TV infection will test negative. If the test shows you have trichomoniasis, it's important that your current sexual partner and any other recent partners are also tested and treated.

How do you get trichomoniasis?

Trichomoniasis is caused by a tiny parasite called Trichomonas vaginalis.  

In women, this parasite mainly infects the vagina and the tube that carries urine out of the body (urethra).

In men, the infection most commonly affects the urethra, but the head of the penis or prostate gland, a gland near the bladder that helps produce semen, can become infected in some cases.

The parasite is usually spread by having sex without using a condom.

It could also be spread by sharing sex toys if you do not wash them or cover them with a new condom before use.

You do not have to have many sexual partners to catch trichomoniasis. Anyone who's sexually active can catch it and pass it on.

Trichomoniasis is not thought to be passed on through oral or anal sex.

You also cannot pass on trichomoniasis through:

  • kissing or hugging
  • sharing cups, plates or cutlery
  • toilet seats

The best way to prevent trichomoniasis is to have safer sex. This means always using a condom when having sex, covering any sex toys you use with a condom, and washing sex toys after use.

Treating trichomoniasis

TV can be easily treated with antibiotics. Occasionally a second course of antibiotics is needed if your symptoms don’t go away. Most men and women are treated with an antibiotic called metronidazole, which is usually taken twice a day for 5 to 7 days.

It's important to complete the whole course of antibiotics and avoid having sex until the infection clears up to prevent reinfection. You should not have sex (even with a condom) until one week after both you and your partner have finished your treatment.

Your current sexual partner and any other recent partners should also be treated.

You can catch TV again

Complications of trichomoniasis

Complications of trichomoniasis are rare, although some women with the infection may be at an increased risk of further problems.

If you're infected with trichomoniasis while you're pregnant, the infection may cause your baby to: 

  • be born prematurely (before the 37th week of pregnancy)
  • have a low birth weight

Diagnosis

Trichomoniasis can sometimes be difficult to diagnose because symptoms are similar to those of other sexually transmitted infections (STIs).

If you think you may have trichomoniasis, you should visit your GP or your local sexual health clinic.

Find your nearest sexual health clinic.

Some GP surgeries offer an enhanced sexual health service for diagnosing and treating STIs. It may be better to visit a sexual health clinic clinic instead because these clinics can carry out accurate tests more quickly.

In some cases, your GP may refer you to a sexual health clinic for tests and treatment if they think you have trichomoniasis.

Examination

If your doctor or nurse suspects you have trichomoniasis, they'll usually carry out an examination of your genital area.

In women, trichomoniasis may cause abnormal vaginal discharge or red blotches on the walls of the vagina and on the cervix (the neck of the womb).

If you are a man with suspected trichomoniasis, your doctor or nurse will examine your penis for signs of inflammation or discharge.

Laboratory testing

After a physical examination, your doctor or nurse may need to take a swab from either the vagina or penis. The swab will be analysed in a laboratory to check for signs of the trichomoniasis infection. It may take several days for the results to come back.

In men, a urine sample can also be tested for trichomoniasis.

If your doctor or nurse strongly suspects you have trichomoniasis, you may be advised to begin a course of treatment before your results come back. This ensures your infection is treated as soon as possible and reduces the risk of the infection spreading.

Notifying sexual partners

If the test shows you have trichomoniasis, it's very important that your current sexual partner and any other recent partners are also tested and treated. The staff at the clinic or GP surgery can discuss with you which of your sexual partners may need to be tested.

If possible, tell your sexual partner and any ex-partners so they can get tested and treated as well. If you don't want to do this, the clinic can usually do it for you (it's called partner notification and the clinic won't reveal who you are).

If you've had trichomoniasis and have been cured, there's no need to tell any future partners.

Treatment

Antibiotics

Trichomoniasis is usually treated quickly and easily with antibiotics.

Most people are prescribed an antibiotic called metronidazole which is very effective if taken correctly. You'll usually have to take metronidazole twice a day, for 5 to 7 days.

Sometimes this antibiotic can be prescribed in a single, larger dose. However, this may have a higher risk of side effects and it's not recommended for pregnant or breastfeeding women as a precaution.

Metronidazole can make you feel sick, be sick and cause a slight metallic taste in your mouth. It's best to take it after eating food. Contact your doctor for advice if you start vomiting, because the treatment won't be effective if you're unable to swallow the tablets.

Don't drink alcohol while taking metronidazole and for at least 3 days after finishing the course of antibiotics. Drinking alcohol while taking this medicine can cause more severe side effects, including:

  • a fast heartbeat or heart palpitations
  • skin flushing
  • nausea and vomiting

A specialist can recommend alternative treatments if metronidazole is unsuitable for you (for example, if you're allergic to it).

Follow-up

If you take your antibiotics correctly, you won't normally need any follow-up tests or examinations for trichomoniasis.

However, you may require further testing to see whether your symptoms are being caused by a different sexually transmitted infection (STI) if your symptoms remain or recur after treatment.

If you have unprotected sex before your treatment is finished, you need to return to your GP surgery or sexual health clinic. You may have become reinfected. You must also return if you:

  • didn't complete your course of antibiotics
  • didn't take your antibiotics correctly (according to the instructions)
  • vomited shortly after taking your antibiotics

You may need more antibiotics or a different form of treatment.

Sexual partners

You should avoid having sex while you're being treated for trichomoniasis, as you may become reinfected.

If you were prescribed a single dose of antibiotics, you need to avoid having sex for 7 days after taking the medication.

It's very important that your current sexual partner and any other recent partners are also tested and treated. If your sexual partner isn't treated, this increases the risk of reinfection.

Prevention

If you've had trichomoniasis and it's been treated, you won't be immune to the infection and could get it again.

Like any sexually transmitted infection (STI), the best way to prevent trichomoniasis is to have safe sex. This means always using a condom.

The following measures will help protect you from trichomoniasis and most other STIs, including chlamydia and gonorrhoea. They'll also help prevent you passing it on to your partner:

  • use condoms (male or female) every time you have vaginal or anal sex
  • if you have oral sex, cover the penis with a condom or the female genitals with a latex or polyurethane square (a dam)
  • if you're a woman and rub your vulva against your female partner's vulva, one of you should cover your genitals with a dam
  • avoid sharing sex toys – if you do share them, wash them or cover them with a new condom before anyone else uses them

If you're not sure how to use condoms correctly, you can read about how to use a condom.

If you've been diagnosed with trichomoniasis, make sure both you and your partner are treated, and that any sex toys you've used are cleaned.

Getting tested

If you're sexually active, go for regular sexual health check-ups. You can get an appointment by visiting your local sexual health clinic.

Find your local sexual health clinic.

If you notice any signs or symptoms of an STI, avoid having sex and visit your GP or sexual health clinic as soon as possible.

Further help and advice

Call the National Sexual Health Helpline on 0300 123 7123 for confidential advice and support 24 hours a day, 7 days a week.



The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk
Last Updated: 24/03/2022 14:15:25