Sexually transmitted infections (STIs) – Non-specific urethritis


Sexually transmitted infections (STIs) – Non-specific urethritis

Non-gonococcal urethritis 

Urethritis is inflammation of the urethra – the tube that carries urine from the bladder out of the body. It is usually caused by an infection.

The term non-gonococcal urethritis (NGU) is used when the condition is not caused by gonorrhoea – a sexually transmitted infection (STI).

NGU is sometimes referred to as non-specific urethritis (NSU) when no cause can be found.

In women, NGU rarely has any symptoms. Symptoms in men include:

a painful or burning sensation when urinating

the tip of the penis feeling irritated and sore

a white or cloudy discharge from the tip of the penis

If you think you have NGU, you should visit your local genitourinary medicine (GUM) clinic or sexual health clinic. These clinics have access to specialist diagnostic equipment that your GP may not have.

It is easy to find sexual health services in your area. Sexual health services are free and available to everyone, regardless of age, sex, ethnic origin and sexual orientation.

Why does NGU happen?

NGU can have a number of possible causes, including irritation to the urethra and STIs. Chlamydia causes up to 43 out of 100 cases of NGU.

There are many cases of NGU where no infection is found. If no cause is found, you will still be offered treatment for possible infection. This is also the case if inflammation is caused by an object such as a catheter in the urethra, or by using creams and soaps around the genitals.

Who is affected?

Urethritis is the most common condition diagnosed and treated among men in GUM clinics or sexual health clinics in the UK.

There are around 80,000 men diagnosed with urethritis every year. It is more difficult to diagnose urethritis in women because it may not cause as many symptoms.

NGU is usually diagnosed after urine and swab tests.

Treating NGU

Antibiotics are usually prescribed to treat NGU. You may be given them before you get your test results.

Antibiotics are also used in cases where NGU is thought to have been caused by an object, cream or soap.

In most cases, only a short course of treatment is needed and symptoms clear up after about two weeks.

The most common antibiotics used are azithromycin and doxycycline (Vibramycin-D).

It is important that past and current sexual partners are also treated, to prevent any infection spreading to others.

After treatment has been completed, and symptoms have disappeared, it should be safe to start having sex again.

Preventing NGU

As NGU is usually caused by an STI, practising safer sex is the best way to reduce the chances of it developing.

Safer sex involves using barrier contraception, such as condoms, and having regular checks at sexual health clinics or GUMs.


NGU can have some complications – for example, the condition can keep coming back.

Other complications include:

reactive arthritis – when the immune system starts attacking healthy tissue, which can lead to joint pain and conjunctivitis

epididymo-orchitis – inflammation of the testicles

Women often have no symptoms of NGU. However, if it's caused by chlamydia and left untreated, it can lead to pelvic inflammatory disease (PID). Repeated episodes of PID are associated with an increased risk of infertility.


Symptoms of non-gonococcal urethritis 

Non-gonococcal urethritis (NGU) can cause different symptoms in men and women. In some cases, NGU does not cause any symptoms at all.

Symptoms of NGU in men

The symptoms of NGU in men can include:

a white or cloudy discharge from the tip of the penis 

a burning or painful sensation when you urinate (pee)

the tip of your penis feeling irritated and sore

a frequent need to urinate

Depending on the cause of NGU, symptoms may begin a few weeks or several months after an infection.

If NGU has a non-infectious cause, such as irritation to the urethra, symptoms may begin after a couple of days. Symptoms that start a day or two after sex are usually not caused by an STI, but testing for STIs is still recommended.

If a current or recent sexual partner informs you that you may have been exposed to a sexually transmitted infection (STI) that can cause NGU, but you don't have any symptoms, don't assume that you do not have NGU. If this happens, it is always recommended that you get tested at your local genitourinary medicine (GUM) clinic or sexual health clinic.

You should still seek treatment if the symptoms of NGU disappear on their own, as there is still a risk you could pass the infection on to someone else.

Symptoms of NGU in women

NGU tends to cause no noticeable symptoms in women unless the infection spreads to other parts of the female reproductive system, such as the womb or fallopian tubes (which connect the ovaries to the womb).

If the infection does spread, a woman may develop pelvic inflammatory disease (PID). PID is a serious health condition that can cause persistent pain. Repeated episodes of PID are associated with an increased risk of infertility.

Some women with PID don't have symptoms. If there are symptoms, they include: 

pain around the pelvis or lower part of your stomach (abdomen) 

discomfort or pain during sexual intercourse that is felt deep inside the pelvis

bleeding between periods and after sex

pain when you urinate

heavy or painful periods

unusual vaginal discharge – especially if it is yellow or green

A few women with PID become very ill with:

severe lower abdominal pain

a fever (high temperature) of 38C (100.4F) or above

nausea and vomiting


Causes of non-gonococcal urethritis 

Non-specific urethritis (NSU) is most commonly caused by an infection, although there are many cases where no cause is found.

Although sexually transmitted infections (STIs) can cause NGU, it does not result from a gonorrhoea infection. Urethritis caused by gonorrhoea is called gonococcal urethritis.


In men, chlamydia is thought to be responsible for up to 43 out of 100 cases of NGU. In women, about 4 in 10 cases of NGU may be caused by chlamydia.

Chlamydia is caused by Chlamydia trachomatis bacteria. It is an STI and is spread during unprotected sex (sex without a condom), including anal and oral sex.

Other infections

A number of other infections can cause NGU.

These include other bacteria that usually live harmlessly in the throat, mouth or rectum. They can cause NGU if they get into the urethra, which is the tube that carries urine from the bladder to the outside of the body. This can occur during oral or anal sex.

Infections that can cause NGU include:

Trichomonas vaginalis – which is an STI caused by a tiny parasite

other bacteria – such as Mycoplasma

a urinary tract infection

the herpes simplex virus – which can also cause cold sores and genital herpes

an adenovirus – which usually causes a sore throat or an eye infection

Non-infectious causes

It is possible for NGU to have a non-infectious cause. This is when something else leads to the urethra becoming inflamed. 

Non-infectious causes of NGU include:

irritation from a product used in the genital area – such as soap, deodorant or spermicide

damage to the urethra caused by vigorous sex or masturbation, or by frequently squeezing the urethra – some men may do this if they are worried they have an infection

damage to the urethra caused by inserting an object into it, such as a catheter – this can be done during an operation in hospital

Sexually transmitted infections (STIs)

Urethritis can be caused by an STI, and is therefore more common among people who are at risk of STIs. This includes people who:

are sexually active

have had unprotected sex

have recently had a new sexual partner


Diagnosing non-gonococcal urethritis 

Non-gonococcal urethritis (NGU) is usually diagnosed after tests have been carried out at a specialist clinic.

If you think you have NGU, you should visit your local genitourinary medicine (GUM) clinic or sexual health clinic. These clinics have access to specialist diagnostic equipment that your GP may not have.

It's easy to find sexual health services in your area. Sexual health services are free and available to everyone regardless of age, sex, ethnic origin and sexual orientation.


Two tests can diagnose NGU – a swab test and a urine test. Either test can be used, although both may be carried out to ensure the diagnosis is correct.

It is recommended that you are also tested for gonorrhoea and chlamydia at the same time as NGU. These are two sexually transmitted infections (STIs) that often cause urethritis.

You may also be offered tests for other STIs, including HIV. It is up to you whether to have these or not, but a test for all infections is recommended. You can discuss this with healthcare professionals at the clinic if you wish.

Swab test

A swab test involves taking a small sample of fluid from your urethra, which is the tube that carries urine from the bladder to the outside of the body. The sample can then be examined under a microscope to look for evidence of inflammation or bacteria known to cause NGU.

The sample is taken using a swab, which is like a small cotton bud with a plastic loop at the end. The swab is not painful, but can feel a little uncomfortable for a few seconds.

Urine test

You will be asked to provide a urine sample, which will be tested for bacteria known to cause NGU, such as chlamydia.

You will be asked not to urinate for around two hours before providing a urine sample, because this can help make the test results more reliable.


Clinics that have microscope facilities will be able to give you some results the same day. Other clinics may need to send the samples to a laboratory for testing – in which case, the test results may not be available for a week or two.

Healthcare professionals at the clinic will tell you how and when you will get your test results, and they will also arrange your treatment.


A responsible romance: getting tested for chlamydia


In this dramatisation, teenage couple Ben and Rosie get tested for sexually transmitted infections, including chlamydia.

Media last reviewed: 16/03/2013

Next review due: 16/03/2015

What happens at a sexual health clinic?

You will be asked about your sexual history – for example, when you last had sex, whether you used condoms and whether you have had an STI before.

If you are attending the clinic for non-gonococcal urethritis (NGU), you will be offered tests for STIs. You do not have to have the tests, but it makes sense to have them. Tests can only be done with your consent.

Staff at the sexual health clinic will be able to advise you about the sexual partners who will need to be contacted, and may be able to contact them on your behalf. If you wish, your anonymity will be protected when contacting your previous sexual partners.


Treating non-gonococcal urethritis 

Non-gonococcal urethritis (NGU) is usually treated with a short course of antibiotics to kill the bacteria that caused the infection.

The healthcare professionals at the genitourinary medicine (GUM) clinic or sexual health clinic will arrange your treatment.

If your urethritis is caused by gonorrhoea, this may be treated differently.


Treatment with antibiotics may be started before you receive your test results (read about diagnosing NGU for information about these tests).

If your test results do not identify an infection, or your NGU is related to inflammation caused by an object, cream or soap, antibiotics are also used frequently. 

Most people with NGU are prescribed antibiotic tablets or capsules. This may be:

azithromycin – which is taken just once as a single dose

doxycycline – which is taken twice a day for seven days

You will usually not need to return to the clinic as long as you have:

taken your treatment

made sure that any recent partners have been treated

not had any sex until a week after everyone has been treated

It may sometimes take two or three weeks for your symptoms to disappear completely.

You should not have sex, including vaginal, anal and oral sex, until:

you have finished your course of doxycycline, or it has been seven days since you took azithromycin

you have no symptoms

your partner or partners have also been treated

Side effects

Antibiotics may cause some side effects, such as:

feeling sick



Antibiotics used to treat NGU may interact with the combined contraceptive pill and the contraceptive patch. If you use these methods of contraception, your GP or nurse can advise you about which additional contraception is suitable.

NGU and sexually transmitted infections (STIs)

While not all cases of NGU are caused by a sexually transmitted infection (STI), it is possible to pass on NGU during sex. Therefore, you should treat all cases of NGU as an STI and ensure that all recent partners have been treated.

You also shouldn't have any kind of sex until you are certain the condition has cleared up.

NGU does not tend to cause any noticeable symptoms in women, but can still affect a woman's long-term health. The bacteria associated with NGU can trigger the development of pelvic inflammatory disease (PID), which is more serous. 

Therefore, you should always tell your current partner and any recent sexual partners if you are diagnosed with NGU. They will also need to be tested and treated for the condition.

Informing partners

It is important that your current sexual partner is tested and treated. Any sexual partners you have had since being exposed to the STI will also need to be informed, so they can be tested and treated.

It is suggested that you inform any person you have had sex with in the last three months, but this timeframe can vary. The healthcare professionals at the GUM clinic can advise you.

Some people can feel angry, upset or embarrassed about discussing STIs with their current partner or previous partners. However, don't be afraid to discuss your concerns with the healthcare professionals at the GUM or sexual health clinic. They can advise you about who to contact and the best way to contact them.

With your permission, the clinic can arrange for a "contact slip" to be given to your former partner or partners. The slip explains that they may have been exposed to an STI and advises them to have a check-up. The slip does not have your name on it, and your details will remain totally confidential.

Nobody can force you to tell any of your partners about your STI, but it is strongly recommended that you do. Left untested and untreated, STIs such as chlamydia can have serious effects on a person's health, particularly for women.

Complications of untreated chlamydia include:

infection of the testicles in men

infection of the cervix (neck of the womb) in women

PID – which can increase the risk of infertility and ectopic pregnancy

Treatment failure

If the symptoms of non-gonococcal urethritis (NGU) do not get better two weeks after you start to take antibiotics, you should return to the genitourinary medicine (GUM) clinic or sexual health clinic.

You will be asked if you took the medication correctly and whether anyone who may have NGU that has not been treated could have passed the infection back to you. 

You may need further tests to confirm your diagnosis and to check for any sexually transmitted infections (STIs

In some cases you may be given a new prescription for some different antibiotics to treat the NGU.


Complications of non-gonococcal urethritis 

Non-gonococcal urethritis (NGU) can have serious complications, although these are rare.

Persistent urethritis

The most common complication of NGU is persistent or recurrent urethritis. This is when you still have urethritis 1 to 3 months after being treated for NGU. This affects 1 or 2 men in every 10 who are treated for NGU, and can affect women too.

If you still have symptoms two weeks after starting a course of antibiotics, you should return to the genitourinary medicine (GUM) clinic or sexual health clinic. 

Reactive arthritis

Reactive arthritis is an uncommon complication of NGU, estimated to affect less than 1 in 100 people with the condition.

Reactive arthritis is caused by the immune system attacking healthy tissue for an unknown reason, rather than the bacteria responsible for NGU.

This can cause:

joint pain

conjunctivitis (inflammation of the eyes)

recurring urethritis


Epididymo-orchitis is a possible complication of NGU in men. It is a combination of epididymitis and orchitis:

epididymitis is inflammation of the epididymis – a long coiled tube in the testicles that helps store and transport sperm

orchitis is inflammation of the testicles

Epididymo-orchitis affects fewer than 1 in 100 men with NGU.

Pelvic inflammatory disease (PID)

In women, pelvic inflammatory disease (PID) can be a result of NSU if left untreated. PID is a serious condition that can increase the risk of infertility and ectopic pregnancy.


Preventing non-gonococcal urethritis 

As most cases of non-gonococcal urethritis (NGU) are caused by a sexually transmitted infection (STI), the best way to protect yourself is to practise safer sex.

Using a condom when you have sex, including vaginal, oral and anal sex, can help prevent you getting or passing on an STI.

Safer sex

There are a number of steps you can take to ensure you are having safer sex, such as:

keeping the number of sexual partners to a minimum

using a barrier method of contraception, such as condoms, every time you have vaginal or anal sex  

covering the penis with a condom or the female genitals with a latex or plastic square (dam) if you have oral sex  

avoid sharing sex toys; if you do share them, make sure you wash or cover them with a new condom before anyone else uses them

You and your partner(s) should have regular check-ups for STIs. If you are not in a stable relationship and are sexually active, you should have a check-up every year. You should have tests more often than this if you have unprotected sex with a new partner, or if you notice any symptoms that worry you.

Testing can be done at your GP surgery, or at a genitourinary medicine (GUM) clinic or sexual health clinic.

You can find sexual health services in your area.

Further help and advice

If you are worried about immediate sexual problems, read about needing help now.

Alternatively, you can call:

Sexual health line on 0300 123 7123 for confidential information and advice on sexual health

Worth Talking About on 0300 123 29 30 for advice on contraception, sexual health and relationships (Mon-Fri 2pm-8pm, Sat-Sun 2pm-4pm)

Brook on 0808 802 1234 for confidential sexual health information and advice for young people under 25 (Mon-fri 11am-3pm)

You can also read and download leaflets about all STIs from the FPA website, or read about sexual health for general information.

Other causes

Not all cases of NGU are caused by an STI. It can also be the result of irritation caused by creams, lotions and objects.

To prevent NGU developing in this way, you should avoid putting anything into the urethra (the tube that carries urine from the bladder out of the body), and stop using creams that cause discomfort around your genitals.