Current strategies to prevent sexually transmitted infections (STIs) are not controlling the epidemic. The efficacy of doxycycline STI postexposure prophylaxis shows promise in pilot studies, but wider acceptability is unknown. A majority (84%) of diverse individuals using a gay social networking application were interested in doxycycline STI postexposure prophylaxis. Doxycycline STI postexposure prophylaxis should be examined in larger trials.