While some people may be concerned that regular use of DoxyPEP may lead to antibiotic resistance, doxycycline has been used for decades to treat syphilis and chlamydia and we have not seen these infections develop any resistance to doxycycline.

It is not yet known however, if and how taking doxyPEP may affect normal/good bacteria in our bodies. Many experts though, believe that this is unlikely to be a significant issue.

There is currently a lack of evidence on the effectiveness of doxyPEP for people how might acquire STIs through receptive vaginal or frontal sex – including women and some trans men.  This does not, however, necessarily mean that it would be ineffective or unsafe to use. If you have concerns around your risks of acquiring bacterial STIs and would want advice on whether doxyPEP would be of benefit to you, please speak to us, or your local sexual sexual health service, for advice.