Urethritis
Non-gonococcal urethritis (NGU) is inflammation of the urethra (the tube that carries urine out of the body) that is not caused by gonorrhoea. It is one of the most common conditions treated in sexual health clinics.
The most frequent infectious causes include Chlamydia trachomatis, Mycoplasma genitalium and Ureaplasma species. In some cases, no specific cause is identified.
Symptoms in men may include a white or cloudy discharge from the tip of the penis, a burning or painful sensation when urinating, and irritation at the urethral opening. Women can carry the same organisms with fewer urethral symptoms.
Diagnosis involves a urine test or urethral swab. Treatment with appropriate antibiotics is effective, and sexual partners should also be tested and treated to prevent reinfection.
Causes of Urethritis
Non-gonococcal urethritis is caused by infection or inflammation of the urethra from causes other than Neisseria gonorrhoeae.
The most common infectious causes are:
- Chlamydia trachomatis, responsible for around 30 to 50% of cases
- Mycoplasma genitalium, an increasingly recognised cause
- Ureaplasma urealyticum and Ureaplasma parvum
- Trichomonas vaginalis (less common in the UK)
- Herpes simplex virus and adenovirus (less common)
In a significant proportion of cases (around 20 to 30%), no pathogen is identified. Non-infectious causes can include chemical irritation from soaps, spermicides or antiseptics, and trauma from catheterisation.
Tests that can help check this condition
Learn more on the official NHS page .
Medical review
Dr. Shahzaib Ahmad MBBS, BSc, MRCP, FRCA, FFICM
Clinical Supervisor - Vitall|GMC 7495062|Profile
Reviewed on 22/05/2026
Next review due 22/05/2027
Review focus: Blood biomarkers, laboratory testing methodology, and biochemical interpretation.
