Venereal syphilis is a chronic cyclic infectious disease that, if untreated, runs a decades-long course. The responsible pathogen is Treponema pallidum. Clinically, a differentiation is made into early (primary) syphilis (up to 1 year following infection, syphilis I), during which disease manifestations are localized, secondary syphilis (syphilis II) with generalized manifestations, and late, or tertiary syphilis (syphilis III). Clinical manifestations that have been observed in HIV patients are syphilis maligna and neurosyphilis. Treatment of choice continues to be penicillin. Instead of only a single injection of penicillin, HIV infected patients with early syphilis should be given three injections, with an interval of 1 week between them, to prevent the development of neurosyphilis.