Sexual Health Advice - Patient Information Leaflets

Non-Specific Urethritis (NSU)

What is non-specific urethritis?

The urethra is the tube between the bladder and the end of the penis. Urethritis means inflammation (pain, redness and/or swelling) of the urethra.

Gonococcal urethritis is caused by a bacterium (germ) called gonorrhoea. This is a type of sexually transmitted infection (STI). A separate leaflet describes gonorrhoea in more detail.
Non-specific urethritis (NSU) is due to causes other than gonorrhoea. This is sometimes called non-gonococcal urethritis (NGU). This leaflet describes NSU further.
Some men have both gonococcal and non-specific urethritis at the same time.

What causes non-specific urethritis?

There are many different causes some, but not all, are passed on through having sex. If you have non-specific urethritis there may be more than one cause. In about 1 in 4 men no cause is found.

Causes of non-specific urethritis include:

Sexually transmitted infections

Chlamydia causes about half cases of non-specific urethritis
Herpes and trichomonas vaginalis are less common causes
Other organisms
Mycoplasma genitalium causes 20% cases of non-specific urethritis and can be transmitted sexually
Ureaplasma urealyticum causes 10% of non-specific urethritis
Some bacteria that live in the rectum, mouth and throat can be passed on during sex and cause non-specific urethritis
Bacteria that cause infection in the urinary tract (kidneys, bladder and urethra) or the prostate can cause non-specific urethritis
A vaginal infection in your partner, such as thrush or bacterial vaginosis may trigger non-specific urethritis in you
Damage to the urethra
This can be caused by friction during vigorous sex, masturbation or inserting objects into the urethra
Antibacterial liquid e.g. tea tree oil, antiseptic or disinfectant can cause inflammation
Rarely, if your skin is sensitive to chemicals e.g. latex, spermicide or soap inflammation

How is non-specific urethritis passed on sexually?

During unprotected vaginal, anal or oral sex, organisms which cause inflammation can pass into the urethra.

Not all cases of non-specific urethritis are caused by having sex. However, you cannot get non-specific urethritis from hugging, kissing, sharing baths or towels or from toilet seats.

What are the symptoms of non-specific urethritis?

Some men do not have any symptoms

If symptoms do occur they usually show up within 2 – 4 weeks of contact with an infection, but sometimes they can appear within a day or two (depending on the cause). In mild cases symptoms may not show up for several months.

If you do get symptoms these may include:

A white discharge (fluid) from the end of the penis

Pain or burning when you pass urine. This may be confused with a urine infection.

Irritation inside the penis.

A feeling of wanting to pass urine frequently.

In a small number of cases the infection travels up the urethra to the testes and causes pain and swelling in one or both testes.

A rare complication is a type of arthritis which can be triggered by non-specific urethritis. It may be due to the immune system ‘over-reacting' to some bacteria that can cause non-specific urethritis.

The symptoms may clear over time, even without treatment. However, without treatment, bacteria that cause non-specific urethritis often remain in the urethra. Therefore, even if symptoms go, there is a good chance that you can pass on the infection if you are not treated.

How will I know if I have non-specific urethritis?

You can only be certain if you have a test. Because the inflammation can be caused by sexually transmitted infections it is recommended that you have a test for Chlamydia and gonorrhoea. The type of sample collected will depend on whether you have any signs and symptoms and what infections you are being tested for. Tests may include:

Examining your penis

Using a swab to collect a sample of cells from the entrance of the urethra

A urine sample

It is possible to be tested within a few days of having sex, but it might be necessary to wait up to 2 weeks before you can do a test to check for infections e.g. chlamydia. You can do a test even if you do not have symptoms. The results of the tests are usually known within 5 days.

What is the treatment for non-specific urethritis?

A short course of antibiotics usually clears non-specific urethritis. The antibiotic prescribed may depend on which bacteria are found (often chlamydia), and whether other infections are also present.

If no bacteria are found by the tests, you may still be advised to take a course of antibiotics if you have symptoms of non-specific urethritis. Infection is still the likely cause, even if a bacterium cannot be identified.

Most people get better with antibiotic treatment. However, for a few men it may keep coming back. If this happens you may be given a second course or combination of antibiotics.

There is no evidence that complementary therapies can cure NSU.

What happens if non-specific urethritis is not treated?

It can cause long term complications including:

Painful infection of testicles

Reduced fertility

Reactive arthritis (inflammation of joints) particularly if this is accompanied by inflammation of the eyes and urethra – this is known as Reiter's syndrome.

You also run the risk of passing the infection on to someone else.

Does my sexual partner need treatment?

Yes. They should be tested for infection, even if they do not have any symptoms. A course of antibiotics is usually advised for sexual partners, even if the tests are negative, because:

Many women who are infected with chlamydia do not have symptoms. If this is left untreated, it can cause complications at a later time such as serious infection of the pelvis (pelvic inflammatory disease) which can result in blocked fallopian tubes and possible future ectopic pregnancy.
Tests for bacteria are not foolproof. A course of antibiotics helps to make sure that any possible infection is cleared.
If your sexual partner is infected and not treated, the infection can be passed back to you.

It is strongly advised that you do not have vaginal, anal or oral sex until you have been told it is fine to have sex again, and after your current partner has finished the course of treatment. If it is not possible to avoid sex, make sure you use a condom.

How will I know how long I have had the infection?

The tests cannot tell you how long the infection has been there. If non-specific urethritis has been caused by a sexual infection and you have had more than one sexual partner, it may be impossible to determine which partner it has come from. This can be difficult to deal with. Do not be afraid to discuss this with the clinic staff about how you feel.

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