DoxyPEP is becoming less effective against gonorrhea as antibiotic resistance rises, even as protection against chlamydia and syphilis remains durable, according to study results published in The Lancet Infectious Diseases. “We report a rapid loss of effectiveness of doxycycline PEP for prevention of gonorrhea in male individuals living with HIV or receiving HIV PrEP or PEP in Southern California,” the authors wrote, noting that their findings might merit revision of guidelines recommending doxyPEP for gonorrhea prevention. DoxyPEP refers to taking a single dose of doxycycline—an antibiotic related to tetracycline—as post-exposure prophylaxis within 72 hours after sex to prevent sexually transmitted...