The treatment of syphilis and other sexually transmitted infections (STIs) is complex. If taken properly, antibiotic treatment with penicillin will usually cure a syphilis infection. If syphilis has progressed to the tertiary stage, antibiotics can prevent further complications. But they cannot reverse damage that has already occurred. Prompt antibiotic treatment will decrease complications and prevent the spread of the infection.
Exposed sex partners should be treated for syphilis. The chancres in syphilis can make transmission of HIV more likely. So testing for both syphilis and HIV should be done.