If taken within 72 hours of condomless sex, the common antibiotic doxycycline drastically reduces the risk of gonorrhea, syphilis and chlamydia among transwomen and gay, bisexual and other men who ...

A promising line of attack against sexually transmitted infections puts a cheap and widely available medication to a new use. The treatment – a form of post-exposure prophylaxis, or PEP – is a dose of ...