Recently, the U.S. Centers for Disease Control and Prevention (CDC) released clinical guidelines on the use of doxycycline postexposure prophylaxis (doxy PEP) for bacterial sexually transmitted infection prevention, calling doxy PEP "a novel, ongoing, patient-managed biomedical STI prevention strategy for a selected population". However, not much is known about the existing use of antibiotics as STI prevention in the U.S. populations that have the potential to benefit from it.