Syphilis is an STI caused by bacteria. The infection can occur in and around the genitals, rectum, or eyes. It can be treated with penicillin. Syphilis can begin with painless sores (known as chancres). If left untreated, it can lie dormant for varying amounts of time (years or sometimes decades) and then resurface, causing life-threatening damage to your heart, brain, and other organs. It can also cause serious complications in pregnancy.


Syphilis symptoms appear in 4 different stages. The stages do not necessarily occur in the same order and can overlap. Syphilis can be spread at any of the first 3 stages and can be spread even if no symptoms are shown.

The first visible chancre appears, usually where the infection entered your body. The sore can be small or may be hidden inside your genitals or rectum, which means you may not see it or know that you’ve been infected. It should heal on its own in about 3–6 weeks. You may also experience swollen lymph nodes near your groin.

About 2–10 weeks after initial infection, you may develop a reddish-brown skin rash that can spread across your entire body and/or sores in your mouth, vagina, or rectum. You may also experience other symptoms, including:

  • Fever and headache
  • Swollen lymph nodes
  • Weight loss
  • Hair loss
  • Fatigue
  • Muscle aches

If left untreated, the symptoms can increase in severity or disappear and then return.

The infection appears to go away, though your body remains infected. Not everyone with syphilis experiences the latent stage, but if you do, it can last for years or even decades.

Most people do not advance to the final stage of syphilis. For those who do, it is the most severe—potentially fatal. It can occur 10-30 years after initial infection. Symptoms during the tertiary stage can include:

  • Damage to your brain, heart, or liver
  • Stroke
  • Numbness
  • Deafness
  • Blindness
  • Inflammation of your blood vessels and/or spinal cord

If the infection enters your nervous system, you may also experience:

  • Dementia
  • Paralysis
  • Aneurysm
  • Personality changes


Syphilis is treated with the antibiotic penicillin. If the infection is caught early, it is usually easy to cure.

When to Seek Medical Attention

If you experience any of the above symptoms, consult with your healthcare provider. If you are sexually active, testing for syphilis may be included in your STI testing. You should discuss your risk factors with your medical provider. Syphilis is generally diagnosed using a blood test. If you test positive for syphilis, it is important to notify all of your past sexual partners.

Causes & Prevention

Syphilis passes from person to person during vaginal, oral, or anal sexual contact. Penetration and/or ejaculation do not need to occur to spread the infection. It is also possible for a pregnant woman to transmit syphilis to her child during pregnancy.

As with all STIs, the only way to avoid all risk of infection if to abstain from sex (vaginal, anal, and oral) and intimate skin-to-skin contact.

If you are sexually active:

  • Use condoms and/or dental dams consistently every time you have sex (anal, oral, or vaginal).
  • Communicate with your partner(s) about STIs, testing and using condoms and/or dental dams.
  • If using sex toys, follow the instructions on how to clean them properly after each use. If they have  no batteries/electrical wires, wash with soap and water and allow to dry.
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