What happens when syphilis is left untreated?

Without treatment, the syphilis infection will stay in your body. It can be latent for years, which means you won’t see any signs or symptoms.

Eventually, it can lead to severe and life-threatening health problems. Untreated syphilis can cause:

  • stroke

  • blindness

  • meningitis

  • heart problems 

  • loss of coordination

  • dementia

Syphilis can still be treated at this stage. But it may not be possible to reverse any damage that’s been done.


Reviewed by Dr Paula Baraitser. Medical Director
Last updated at: 22 June 2023