How much does STI treatment cost in London? NHS vs private explained

The short answer: NHS STI treatment is free at sexual health clinics for everyone in the UK — regardless of GP registration, immigration status, or whether you've used NHS services before. That includes the consultation and the medication dispensed at the clinic.

But there are important nuances. Treatment costs differ depending on where you get treated, which infection you have, and whether you have a confirmed diagnosis first — which you always need. This guide covers what treatment actually costs per infection, when private makes sense, and why testing before treatment isn't optional.

Every STI is treated differently. Some require a single antibiotic dose. Others need specialist referral and long-term management. Here is what treatment typically costs for each common infection.

NHS sexual health clinics — also called GUM (genitourinary medicine) clinics — provide completely free STI testing, consultation, and treatment for everyone in England. No GP registration needed. No proof of residency. You can attend anonymously at most clinics.

In London, the main options include 56 Dean Street in Soho, Burrell Street Clinic in Waterloo, and local borough sexual health clinics across all 32 boroughs. The limitation is waiting time. Busy clinics can have walk-in queues of several hours, and booked appointments are not always available on the same day.

If your GP prescribes STI treatment rather than referring you to a sexual health clinic, standard NHS prescription charges apply — currently £9.90 per item in England. People with low income, chronic conditions, or aged under 16 or over 60 may be exempt.

For most people, NHS treatment is the right route. Private treatment makes sense in specific circumstances:

• You cannot wait — for example, gonorrhoea treatment before a partner is notified, or chlamydia treatment before symptoms worsen
• You have a confirmed private test result and want to avoid attending an NHS clinic for privacy reasons
• NHS appointment availability is poor in your area and the infection requires prompt treatment
• You are travelling and need documentation of clearance

For HIV, late-stage syphilis, and hepatitis C, private treatment is either impractical or very expensive. The NHS is the appropriate route for all three — and NHS specialist services for HIV and hepatitis C are among the best in the world.

No responsible clinic — NHS or private — will prescribe STI treatment without a confirmed diagnosis. There are two reasons for this.

Different infections require different treatments. Chlamydia and gonorrhoea cause similar symptoms but are treated with different drugs. Taking the wrong antibiotic achieves nothing, and contributes to resistance — which is already a serious problem with gonorrhoea specifically.

Most STIs have no symptoms. The majority of people with chlamydia, gonorrhoea, HIV, and syphilis do not know they are infected. Treating without a confirmed result is not clinically appropriate.

The practical route for most people is to test privately for speed and discretion, then treat via NHS for cost. You attend MDC, receive results within 24–42 hours, and take a confirmed positive result to an NHS sexual health clinic for free treatment. It separates the privacy-sensitive step from the treatment step — which is exactly why many patients prefer it.

No reputable clinic will prescribe STI treatment without a confirmed result. Some pharmacies offer azithromycin for chlamydia to contacts of confirmed cases — this is a specific exception that requires confirmation that a partner has tested positive. In all other situations: test first, treat after.

Treatment at an NHS sexual health clinic is confidential and separate from your GP record. The clinic will not inform your GP of your visit, diagnosis, or treatment unless you ask them to or there is a specific clinical reason. If your GP prescribes treatment directly, it will appear on your NHS record in the usual way.

Chlamydia: symptoms typically resolve within 1–2 weeks of completing antibiotics. Gonorrhoea: symptoms usually clear within a few days of the injection; test of cure at 2 weeks is recommended. Syphilis: penicillin clears the infection with follow-up blood tests confirming clearance at 3 and 6 months. Herpes: antivirals reduce outbreak severity but do not clear the virus.

NHS testing and treatment are free and available to everyone — the clinical quality is equivalent to private. Westminster residents attending MDC receive 20% off all sexual health tests, which reduces private testing costs significantly. See our full sexual health test list and pricing.

MDC is a diagnostic testing clinic. We provide the test and the confirmed result. We do not dispense prescription medication or administer injections on site. If you test positive, our clinical team advises on next steps — including which NHS clinic to attend for free treatment, or how to access a private GP if you prefer. For most patients, testing privately at MDC and treating via NHS is the most cost-effective and discreet combination.