Superdrug has become the first high street pharmacy in the United Kingdom to offer a preventative antibiotic, known as DoxyPEP, aimed at reducing the spread of sexually transmitted infections (STIs). The treatment is available for £10.99 for a single 100mg dose, with a 20-tablet course costing £19.99. This initiative comes as STI cases continue to rise across the UK, with experts pointing to changing sexual behaviors and increasing treatment resistance as contributing factors.
DoxyPEP has demonstrated effectiveness in cutting the risk of syphilis and chlamydia by up to 80 percent when taken within 72 hours of unprotected sex. For optimal results, two 100mg capsules are recommended within 24 hours of exposure. If multiple instances of unprotected sex occur within the 72-hour window, a single 100mg dose is advised at the end of that period. Timing is considered crucial, with earlier administration within the window being generally recommended.
This preventative measure is not for individuals already experiencing STI symptoms but is targeted at specific at-risk groups. These include men who have sex with men, transgender women, sex workers, individuals diagnosed with a bacterial STI in the past year, and those reporting higher-risk sexual behaviors such as group sex. To access the medication, patients must complete an online consultation to determine suitability.
The drug, which is already utilized by the National Health Service (NHS) to treat existing bacterial STIs like syphilis, gonorrhea, and chlamydia, is designed for bacterial infections. A real-world study published last year involving over 2,200 participants found that those taking DoxyPEP experienced a 79 percent reduction in chlamydia risk, an 80 percent reduction in syphilis risk, and a 12 percent reduction in gonorrhea risk.
Chlamydia remains the most common STI in the UK, accounting for nearly half of all diagnoses in 2025, followed by gonorrhea and genital herpes. Left untreated, chlamydia can lead to serious health issues, including pelvic inflammatory disease and infertility. The article emphasizes that no single intervention can completely eliminate STI risk and that regular testing remains essential. DoxyPEP is presented as a complementary option to existing sexual health measures. Common symptoms of STIs include unusual discharge, pain during urination, and sores around the genital area. STI testing is available free and confidentially through sexual health clinics and self-sampling kits.