The treatment of syphilis is determined by the length of time the person has been infected. Primary, secondary, and latent syphilis of less than 1 year duration is treated as follows:

• Benzathine penicillin 2.4 million units injected into a muscle (IM) as a single dose.
• Doxycycline 100 mg by mouth twice per day for 2 weeks.
• Tetracycline 500 mg by mouth 4 times per day for 2 weeks.
• Erythromycin 500 mg by mouth 4 times per day for 2 weeks.
• Ceftriaxone 250 mg IM (intramuscular injection) daily for 10 days.

• Benzathine penicillin 2.4 million units IM weekly for 3 weeks.
• Doxycycline 100 mg by mouth twice per day for 30 days.
• Tetracycline 500 mg by mouth twice per day for 30 days.

• Aqueous penicillin G 12 to 24 million units injected into a vein (IV) daily for 10 days followed by benzathine penicillin 2.4 million units once a week for 3 weeks.
• Procaine penicillin 2.4 million units IM daily given with oral probenecid 500 mg 4 times per day -- both for 10 days.

To treat syphilis during pregnancy:

Penicillin is recommended as the only drug of choice. Tetracycline cannot be used because of toxicity to the fetus, and erythromycin may fail to prevent congenital syphilis in the fetus. Penicillin-allergic individuals should be desensitized and then treated with penicillin.

Several hours following treatment of early stages of syphilis, some individuals may undergo a febrile reaction called Jarisch-Herxheimer reaction. This is thought to be caused by the release into the circulation of material from dead or dying spirochetes. Symptoms of this reaction include:

• Fever
• Chills
• Headache
• Nausea
• General feeling of being ill (malaise)
• Generalized joint aches (arthralgia)
• Generalized muscle aches (myalgia)

These symptoms usually disappear within 24 hours.

Follow-up blood tests must be done at 3, 6, 12, and 24 months to ensure that the infection has been eliminated.

Individuals with primary or secondary syphilis should abstain from sex until they have been treated. Syphilis is extremely contagious in the primary and secondary stages.

Late syphilis may be permanently disabling and may lead to death.

• Cardiovascular syphilis
• Aneurysms
• Valvular heart disease
• Neurosyphilis
  • tabes dorsalis
  • general paresis
  • optic nerve atrophy or optic neuritis

Untreated syphilis can result in serious health problems. It is imperative that you inform your physician of the possibility of having had syphilis previously, even if it was many years ago.