An old antibiotic may get new life as an STI prevention pill

A potent new tool in the ongoing battle against sexually transmitted infections is about to be introduced by the United States: a well-established antibiotic from decades past that has been repurposed into a preventive pill.

DoxyPEP, or doxycycline used as a post-exposure prophylaxis, has been found to significantly cut the risk of chlamydia, gonorrhea and syphilis when used after condomless sex.

The Center for Disease Control and Prevention (CDC), which is developing national guidance for clinicians, will need to weigh the need to contain record high rates of STIs impacting millions of Americans against potentially giving rise to more antibiotic-resistant strains.

"Innovation and creativity matter in public health, and more tools are desperately needed," senior CDC official Jonathan Mermin told AFP.

But the recommendations, set for publication this summer, will remain narrow in scope.

They will likely target only the most at-risk groups of gay men and transgender women with histories of prior infection.

As word spreads, some clinics are already prescribing DoxyPEP.

Malik, a 37-year-old man in Washington, said his doctor recently told him he could start using doxycycline as a "morning-after pill" following risky sex, something he's had to do twice -- including after a partner did not warn him he had removed his condom.