Non Specific Urethritis (NSU) is the name given to inflammation of a man’s urethra (water passage) when the cause is not yet known. Of the 100,000 cases per year in the UK, most are caused by sexually transmitted infections (STI) transmitted through unprotected oral, vaginal or anal sex but in 30% of cases, no infection can be found.

The cause may be caused by gonorrhoea, chlamydia, Trichomonas vaginalis, Mycoplasma genitalium, Herpes Simplex 1 and 2 (the cold sore virus), adenovirus, gut bacteria, chemical or other irritants. NGU cannot be caught by kissing, from swimming pools, by sharing towels, saunas or from toilet seats.

Men will usually notice a discharge from the tip of the penis, a burning pain when passing urine, irritation or itching at the tip or opening of the penis

In women whose male sexual partner has NSU caused by an STI, she may notice vaginal bleeding after sex or between periods, pain in the lower abdomen, an abnormal vaginal discharge or pain when passing urine

The diagnosis in men is confirmed with a swab from the urethra and the cause confirmed by a urine test. Women whose male sexual partner has been diagnosed with NSU should be tested as well

NSU is treated with antibiotics, usually doxycycline or azithromycin in the first instance but this may be adjusted if the infection turns out not to be Chlamydia.

As NSU may be caused by an STI it is important that all current sexual partner(s) are tested for STIs

Whether treated with a seven day course of antibiotics or a single does antibiotic you should not have sex (including sex with condoms and oral sex) until one week after the start of treatment

To prevent a re-infection all current sexual partners must be treated before having sex with them again. Protect yourself with new partners by using a condom for all anal, oral and vaginal sex.