Antisyphilitic drugs are medications specifically used to treat syphilis, a sexually transmitted infection caused by the bacterium Treponema pallidum. The primary treatment for syphilis is penicillin, an antibiotic that effectively kills the bacteria and helps prevent complications associated with the disease. In addition to penicillin, other antisyphilitic drugs may be used for patients who are allergic to penicillin or have specific treatment needs. These alternatives include doxycycline and tetracycline. Early diagnosis and treatment are crucial to prevent the progression of syphilis and its potential long-term health effects.