STI symptoms but a negative test? What to do next

The result says negative, but the burning, the discharge or the soreness is still there. It's frustrating, but there's usually an explanation. A negative test with symptoms that keep going usually comes down to one of four things: it was taken too early, the wrong site was sampled, the infection wasn't on the panel, or the cause isn't a sexually transmitted infection at all.

Repeating the same test tends to give the same answer. What helps is a doctor looking at what's there and choosing the next test from that. If you'd like to get on with it, book an appointment at our sexual health clinic at 117a Harley Street, seven days a week.

Why do symptoms continue after a negative test?

Most cases fall into one of five explanations, and each leaves a different clue:

Timing catches a lot of people out. Each infection needs a while before a test can see it, and the doctor will give you a retest date based on when you were last at risk. Our guide to STI window periods sets out the usual timings.

Which infections can a standard screen miss?

A chlamydia and gonorrhoea test covers chlamydia and gonorrhoea. Several other organisms can cause similar symptoms and need their own test. We test for Mycoplasma genitalium and Ureaplasma at £120.63 each, or £156.25 for both from one sample, and Trichomonas at £120.63.

Sample site matters just as much. A throat swab, at £104 per site with results in 2 to 3 days, only finds an infection if it's taken, so a throat infection won't show up on a urine result. And sometimes there's inflammation with no single organism behind it, called non-specific urethritis (NGU), which can keep symptoms going after a clear screen.

If you'd like to read more about one of these infections, our sister clinic, Sexual Health Clinic London, explains the Mycoplasma genitalium test in detail. Here, individual STI tests can be added on their own once the doctor has decided which are relevant.

Could it be something other than an STI?

It can be. A urinary tract infection can cause burning or an urge to pass urine without any discharge. Bacterial vaginosis and thrush can cause discharge, odour or itching, and neither is sexually transmitted. Some skin conditions cause soreness or a rash with no infection involved.

If a urine infection looks likely, we start with a urine dipstick at your first visit, and if that shows anything, the sample can go on for a culture or a full STI screen. Our UTI or STI article explains how to tell the two apart.

What happens at the appointment?

A private GP appointment or sexual health consultation starts with your history and an examination, so the doctor works from what's actually there rather than from symptoms alone. Extra tests, such as a throat swab, Mycoplasma genitalium or Ureaplasma, are added only when the history and examination point that way.

For men with discharge, the penile discharge assessment brings examination, testing and treatment together in one visit.

How much does it cost?

A GP consultation is £150. Sexual health screening packages range from £250 to £665, and the Bronze package (£250) includes the consultation. Individual tests start from £68, and a throat swab is £104 per site.

If you'd rather not wait days for an answer, FAST Simple (£350) and FAST Complex (£450) return results in 6 hours. Most other urine and swab tests take up to 3 working days, a throat swab 2 to 3 days, and blood tests are usually back within 24 hours.

Should my partner be tested?

If an infection is found and treated, an untreated partner can pass it straight back, and that can look as if the first test was wrong. Your doctor will talk through whether your partner needs testing and when to retest, depending on which infection was found, if any, and how it was treated.