G 3–4 million units every four hours for 10 to 14 days. One daily intramuscular injection and oral probenecid four times daily, both for 10 to 14 days. Follow-up blood tests are generally performed at 3, 6, 12, 24, and 36 months to make sure the infection is gone. Lumbar punctures for CSF fluid analysis are generally performed every 6 months until cell counts normalize. All patients with syphilis should be tested for HIV infection. All cases of syphilis should be reported to public health authorities and public health departments can aid in partner notification, testing, and determining need for treatment. The treatment success is measured with a 4-fold drop in the nontreponemal antibody test. In early-stage syphilis drop should occur in 6–12 months. in late syphilis drop can take 12–24 months. Titers may decline more slowly in persons who have previously had syphilis. In people who cannot take penicillin it is uncertain if other antibiotic therapy is effective for treating neurosyphilis. References Sexually transmitted diseases and infections Syphilis Disorders causing seizures Syndromes affecting the nervous system