What Problems Can Syphilis Cause?

Syphilis is a sexually transmitted disease (STD). It’s easily treated with antibiotics. If you have syphilis and don’t get treated, the infection can lead to a number of serious -- even life-threatening -- conditions. They develop over many years and may include:

  • Heart disease
  • Nervous system disorders
  • Mental disorders
  • Blindness
  • Aortic aneurysms

Pregnancy Complications

If you have syphilis and are pregnant, you can pass it on to your unborn child. You might also have a higher risk of miscarriage, stillbirth (your baby being born dead), or your newborn dying within a few days.

Untreated babies who are born with syphilis can also have problems with their bones, blood, liver, spleen, brain, and skin. It may also cause blindness, seizures, developmental delays, and deafness.

Increased HIV risk

If you have syphilis, you’re up to 5 times more likely to get HIV. That’s because syphilis sores can be open, making it easy for HIV to get into your body while you’re having sex.


These are small bumps of dead tissue and fiber. They can form throughout your body if you don’t get treated. You can get them in your internal organs and on bones or skin in the late stages. They typically go away with treatment.

Neurological Problems

If it’s not treated, syphilis can cause problems with your nervous system. Symptoms include:

  • Severe headache
  • Stroke
  • Loss of muscle coordination
  • Paralysis or inability to move part of your body
  • Numbness
  • A mental disorder called dementia
  • Blindness or changes to vision
WebMD Medical Reference Reviewed by Melinda Ratini, DO, MS on May 20, 2021



CDC: “Syphilis – CDC Fact Sheet.”

Cleveland Clinic: “Syphilis.”

Mayo Clinic: “Syphilis.”

National Institutes of Health: National Institute of Child Health and Human Development: “Sexually Transmitted Diseases: Condition Information.”

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