Syphilis: Symptoms, Treatment, & Diagnosis

By Gila Lyons
Medically reviewed checkmarkMedically reviewed
November 25, 2019

For a disease that was first recorded in the 1490s – it is thought the French spread it throughout Italy during the French invasion – syphilis has proven it can stick with the times. The year 2018 saw 115,045 new reported diagnoses of syphilis, a sexually transmitted infection caused by the bacteria Treponema pallidum. Syphilis first causes sores and rashes, and if left untreated can cause serious health consequences like organ damage and blindness. Fortunately, syphilis can be effectively treated with antibiotics.

What Is Syphilis?

You can catch syphilis when you come into contact with a chancre, or a sore from syphilis, on someone else’s body. Chancres often occur on the genitals, the anus, or in or around the mouth. Because of this, syphilis is transmissible through vaginal, anal, or oral sex. Pregnant women who have syphilis can also give the infection to their child in utero.

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Syphilis Symptoms

Some have nicknamed syphilis “The Great Pretender” since its symptoms–sores and rashes, fever and muscle aches–can seem like other diseases. But the infection progresses in the following way, with four distinct stages:

  • Primary stage: A sore (called an ulcer or chancre) appears that can look like a cut or an ingrown hair. You are most contagious when the ulcer is present. There can be one sore or many, and they are usually painless, firm, and round. The sore generally appears about 21 days after exposure to syphilis but can range anywhere from 10 to 90 days. The initial chancre or chancres will resolve within three to six weeks, whether or not they’re treated. The infection will not resolve without appropriate antibiotic treatment.
  • Secondary stage: In this stage, a rough, red rash appears on one or many areas of the body. It is not itchy or painful, and it can sometimes be so light it is unnoticeable. In this stage, you could develop reddish-brown spots on the palms of your hands or soles of your feet, or develop large grey or white lesions around your groin, mouth, nose, or armpits. This stage can also include hair loss, sore throat, fever, headaches, fatigue, and swollen glands. These secondary stage symptoms can appear right after the primary stage, or several weeks or months later. These symptoms will also resolve on their own with or without treatment in about four to six weeks. However, once again, if not treated you remain infected.
  • Latent stage: The third stage is called the latent stage because symptoms often disappear. This stage can last many years. In this stage, syphilis is usually no longer contagious. However, if left untreated you could suffer more serious health consequences.
  • Late stage or Tertiary Syphilis: Only about 15% of people with untreated syphilis will progress to this final stage, which can occur 10 to 30 years after infection. This stage of syphilis can be fatal as it causes serious issues in different organs like the heart, brain, eyes, ears, and nervous and muscular systems. Some symptoms of this tertiary stage include dementia, vision problems or blindness, trouble controlling muscular movements, and numbness in various parts of the body.

Syphilis Risk Factors

Anyone who has unprotected vaginal, anal, or oral sex can get syphilis. People at increased risk include:

  • Those with multiple sex partners.
  • Those who don’t use condoms consistently or correctly.
  • Those who have sex with a partner who has multiple partners.
  • Men who have sex with men.
  • Those living with HIV and are sexually active.

Syphilis Diagnosis

If you are in the primary or secondary stage of syphilis, a physician or other healthcare provider may be able to diagnose you by looking at your sores or rashes. Others may scrape the chancre and study the cells under a microscope to look for spirochetes (the bacteria that causes syphilis). You can also be diagnosed through blood tests.

Because syphilis can have serious consequences to unborn babies, women are routinely screened by blood tests during pregnancy. Women at a higher risk for the disease are often tested several times throughout their pregnancy and again at delivery.

Syphilis Treatment

There are various treatment options for syphilis depending on the stage of disease. Both late and early stages can be effectively treated with an injection of the antibiotic penicillin. If you’re allergic to penicillin, there are other antibiotic choices.

It’s important to wait to have sex until syphilis sores are completely healed. Unfortunately, having syphilis once does not give you immunity from becoming infected again. Even if you’ve had syphilis and been successfully treated, if you become reinfected you must be treated again.

Syphilis Prevention

There are steps you can take to decrease your risk of exposure to syphilis:

  • Get tested and have your new partner tested before having sex with them.
  • Avoid having sex with someone who has syphilis chancres or symptoms of other STDs.
  • Use male and/or female condoms for genital intercourse, dental dams for oral sex, and latex gloves for manual stimulation. Note that if someone has a syphilis sore that is outside the condom, you can still become infected while using a condom correctly.
  • Avoid sex when under the influence of alcohol or drugs.

If you’ve been diagnosed with syphilis or other STDs, let your partner(s) and past partner(s) know right away so they can be tested and treated if necessary.

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When to See a Doctor

If you are sexually active and see warts, lumps, bumps, or sores in your genital or anal areas, or feel them in your throat or mouth, it’s important to see a medical professional for accurate diagnosis and effective treatment. Specifically, make sure to see a doctor if you:

  • See sores around your genital or anal areas.
  • Notice an unexplained rash that lasts more than one or two days.
  • Notice a rash on the palms of you hands or the soles of your feet
  • Experience joint swelling, fever, or any new symptoms during or after being treated for syphilis.

If you are concerned you might have syphilis or have questions about your symptoms, you can use KHealth to learn more, and chat with a doctor.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Gila Lyons

Gila Lyons' health writing has appeared in The New York Times, Oprah Magazine, Vice, Cosmopolitan, Health Magazine, Healthline, and other publications. Connect with her at