What is syphilis?

A photo of Naveen Puri
Medical Director, Bupa UK Insurance
25 January 2022
Next review due January 2025

Syphilis is a sexually transmitted infection (STI). Like other STIs, such as chlamydia and gonorrhoea, it can be passed on during unprotected sex.

Syphilis cases have increased in recent years in the UK. The number of infections rose from around 3,300 in 2013, to around 7,500 in 2018.

Syphilis can cause serious health problems if it’s not treated. Here I’ll describe how to recognise the signs of syphilis, and what you should do if you think you may have it.

a man talking to a doctor

What are the symptoms of syphilis?

Syphilis has different symptoms at different stages. You may also not get any symptoms at all from syphilis, or you may not notice them.

Primary syphilis

The first syphilis symptom you may notice is one or more ulcers around your genitals. These are known as chancres (pronounced ‘shankers’).

Chancres tend to develop between a few weeks and three months of being in contact with an infected person. They might be on your penis, your vagina, or around your anus. Sometimes they can appear in other areas, like your mouth.

There’s usually only a single ulcer that is painless. But sometimes the ulcer is painful, or there might be more than one.

Secondary syphilis

Several weeks after the primary (first) stage of syphilis, the infection can affect other parts of your body. You may have:

  • a flat, red rash
  • patchy hair loss
  • wart-like growths around your genitals


You might also start to feel generally unwell, with headaches and a fever. Sometimes this can happen earlier, at the same time as having an ulcer.

Latent syphilis

The next stage of syphilis is a latent (hidden) phase. In this phase, you don’t have any signs or symptoms. You may still be infectious, particularly if you were infected less than two years ago. Within two years of infection, you may also revert from latent to secondary syphilis.

Tertiary (late) syphilis

In the late stage of syphilis, the infection causes more serious health problems. These can include loss of vision, heart problems, and problems affecting your brain and nervous system. These complications can be hard to treat. This stage can happen after many years of having untreated syphilis.

What causes syphilis?

Syphilis is a bacterial infection. You can get it by having unprotected sex with an infected person. It’s passed on by direct contact with an infected ulcer.

Anyone who is sexually active can get syphilis. In the UK, most infections are currently among men who have sex with men. It’s also possible to pass syphilis on to your unborn baby if you’re infected while pregnant.

Syphilis was very common a few centuries ago. It became very rare by the 1980s because of better treatment and more people using condoms. But rates have been rising rapidly again over the last twenty years.

When should you get tested for syphilis?

It’s important to get tested for STIs as soon as you can if you think you might have symptoms. You should also have a test if you think you could have been exposed to an STI, even if you don’t have symptoms. This might be if you’ve had unprotected sex with a new sexual partner, or if a regular sexual partner tells you they have an STI.

How do you get tested for syphilis?

You’ll need to do a blood test to check for syphilis. There are several ways to get a syphilis test. You can go to a genitourinary medicine (GUM) or sexual health clinic, or you can ask at your GP practice. You can also pay for tests at a private clinic. In some areas, you may be able to get a test that you can do at home from your local sexual health service.

If you’re infected with syphilis, tests won’t always be able to detect it straight away. It may take up to three months from when you are infected. Your doctor will help you understand whether you need to have another test three months after the suspected date you were exposed to syphilis. This is just to make sure the test isn’t done too early.

How is syphilis treated?

Syphilis is treated with antibiotics. You usually have this as an injection, but sometimes you may take tablets. If you’re diagnosed at a later stage of the disease, you may need to have several injections or take tablets for longer. Syphilis treatment is usually very effective, if you have it early enough.

Telling others

It’s important to let any current and recent partners know that you have syphilis. The staff at a sexual health clinic can help you to do this, while keeping your details confidential. You’ll need to avoid having sex again until at least two weeks after you’ve finished treatment.

How can I reduce my risk of syphilis?

There are many things you can do to lower your risk of getting or passing on syphilis, as well as other STIs.

  • Use a condom during vaginal, oral, or anal sex with the penis.
  • Use a latex square (dental dam) to cover the anus and vaginal opening during oral sex, including the area around it.
  • Don’t share sex toys. If you do, wash them well, or cover them with a new condom before anyone else uses them.
  • Before you have unprotected sex with somebody new, have a test for syphilis and other STIs.

We offer a range of sexual health services within our Bupa Health Centres. So whether you have symptoms and need to speak to a GP or don't have symptoms but want a check to see if you currently have an STI we have a check to suit you. Any customers who test positive receive a follow up with a GP and support from our 24/7 Nurse HealthLine. Learn more today.

A photo of Naveen Puri
Dr Naveen Puri
Medical Director, Bupa UK Insurance

    • O'Byrne P. Syphilis. BMJ 2019;365: l4159. DOI: 10.1136/bmj.l4159
    • Syphilis. NICE Clinical Knowledge Summaries., last revised December 2019
    • Addressing the increase in syphilis in England: PHE Action Plan. Public Health England., published June 2019
    • Rayment M, Sullivan AK. “He who knows syphilis knows medicine” – the return of an old friend. Br J Cardiol 2011;18: 56-8
    • Sexually transmitted infections and screening for chlamydia in England, 2020. Public Health England., published September 2021
    • Syphilis. Sexwise., last updated December 2020
    • Kingston M, French P, Higgins S, et al. UK national guidelines on the management of syphilis 2015. Int J STD AIDS 2016;27(6): 421-46. doi: 10.1177/0956462415624059
    • Tampa, M et al. Brief history of syphilis. J Med Life. 2014 (7,1): 4-10

About our health information

At Bupa we produce a wealth of free health information for you and your family. This is because we believe that trustworthy information is essential in helping you make better decisions about your health and wellbeing.

Our information has been awarded the PIF TICK for trustworthy health information. It also follows the principles of the The Information Standard.

The Patient Information Forum tick

Learn more about our editorial team and principles >

Content is loading