Syphilis: symptoms, testing, treatment and pregnancy

The NHS says the symptoms of syphilis are often mild and hard to notice when you are first infected. They tend to change over time and may come and go. You may have no symptoms you notice at all.

Symptoms you may notice at first include small sores (ulcers) on the penis, vagina or around the bottom (anus), which are usually painless and of which you may have only one. Sores can also appear in other areas, including the mouth, lips, hands or bottom. The NHS says you may not notice sores inside the bottom or vagina if they are not painful.

• White or grey warty growths, most commonly on the penis, vagina or around the anus.

• A rash on the palms of the hands and soles of the feet that can sometimes spread all over the body and is not usually itchy.

• White patches in the mouth.

• Flu-like symptoms, such as a high temperature, headaches and tiredness.

• Swollen glands.

• Patchy hair loss on the head, beard and eyebrows.

The NHS says it can take 3 weeks or more for the first symptoms to appear after you are infected, and you may get the later symptoms up to 3 months later. The UK Health Security Agency (UKHSA) says syphilis is most infectious in its primary and secondary stages, which occur between 2 weeks and 3 months after infection, and that it is generally considered infectious for up to 2 years after initial infection.

Importantly, the NHS says symptoms can improve or go away completely, but if you have not been treated the infection is still in your body. You can still pass it on and you are at risk of serious problems later on.

The NHS says syphilis is treated with antibiotics, which you may have as injections, tablets or capsules. Treatment may be started before your test result is known, and how long you need treatment depends on the stage of your syphilis.

In some people, treatment can cause flu-like symptoms such as a high temperature, headache and aching muscles, usually within the first 24 hours. You will need to go back to the GP surgery or sexual health clinic several times in the first 12 months after starting treatment to be retested.

The NHS says not to have sex (vaginal, anal or oral) until 2 weeks after you and your partner have finished treatment.

UKHSA describes syphilis as an STI caused by the bacterium Treponema pallidum, which in most cases is transmitted by direct contact with an infectious sore. The NHS says the most common way of getting it is unprotected vaginal, anal or oral sex with someone who is infected, through contact with an ulcer on the penis, vagina, bottom or inside the mouth.

It is also possible for syphilis to be passed on to an unborn baby during pregnancy (congenital syphilis), by injecting drugs with a needle used by an infected person, and, rarely, through a blood or organ transplant. The NHS says transplants are a rare route because all blood and organ donations in the UK are checked for syphilis. UKHSA adds that it can be acquired by sharing sex toys.

Having a test is the only way to confirm syphilis, says the NHS. Tests for STIs are free on the NHS and you can go to a sexual health clinic or see a GP. You can also be tested during a pregnancy appointment, or with a self-test kit that you use at home and send to a lab, which you may be able to order from your local STI service or buy at a pharmacy.

If you have symptoms, a doctor or nurse will check the penis, vagina and bottom for sores, and may use a swab to collect fluid from any sores. They will check the rest of your body for rash, sores or wart-like growths and may take a blood sample. You may also be tested for other STIs at the same time.

• Go to a sexual health clinic or see a GP if you or a sexual partner have symptoms.

• Go if a sexual partner has told you they have syphilis or another STI.

• Go if you have recently had sex with a new partner without a condom.

• Go if you are pregnant or planning to get pregnant and think you might have syphilis.

• Go if you have injected drugs using a needle that may have been used by someone with syphilis.

The NHS says untreated syphilis can cause serious and potentially life-threatening problems, and that some may not appear for many years after infection. UKHSA says that if left untreated, about one-third of cases progress to serious complications, while others remain latent for life.

The NHS says that if you are pregnant and have syphilis, you can pass it on to your baby before they are born, which is known as congenital syphilis. Having syphilis during pregnancy can also increase the risk of miscarriage, premature birth and stillbirth.

You will be offered screening for syphilis if you are pregnant, so it can be found and treated before it causes serious problems. If you think you may have been exposed, the NHS says to get tested if you are pregnant or planning to get pregnant.

If you have syphilis, the NHS says your current and any recent sexual partners also need to be tested and treated. A GP or sexual health clinic can advise on contacting them, and this can be done without naming you. UKHSA estimates that around 1 in 3 sexual contacts of a case will develop the infection.

The NHS says to use a condom for vaginal or anal sex, use a condom to cover the penis or a latex or plastic square (dam) for oral sex, wait 2 weeks after completing treatment before any sexual contact, not share sex toys (or wash them and cover them with a new condom before anyone else uses them), and not share needles if you inject drugs.

UKHSA says rates of syphilis in England remain high, and that the number of infectious syphilis diagnoses has increased by 55.4% between 2015 (5,313) and 2025 (8,262). Regular testing is advised if you have new or multiple partners, because symptoms may be mild or absent.

NHS sexual health clinics and GPs provide free testing and treatment, and clinics can also help with partner notification. Postal self-test kits are available from some local services or pharmacies.

Private clinics also offer testing and treatment. Whichever route you choose, follow-up blood tests in the first 12 months are part of care, partners need to be told, and results can be shared with your GP if you wish. A private test does not remove the need for treatment and partner notification.