Study finds doxycycline reduces sexually transmitted infections by two-thirds

The oral antibiotic doxycycline prevented the acquisition of sexually transmitted infections (STIs) when tested among men who have sex with men (MSM) and transgender women who took the medication within 72 hours of having condomless sex, according to findings published today in the New England Journal of Medicine. Specifically, the post-exposure approach, termed doxy-PEP, resulted in a two-thirds reduction in the incidence of syphilis, gonorrhea, and chlamydia among the study participants, all of whom reported having an STI within the previous year. However, the research also revealed a slight increase in antibacterial resistance that requires further exploration, the authors found.