Abstract
Effective treatment of sexually transmitted infections (STIs) such as gonorrhoea and chlamydia needs sexual behaviour modification, in addition to antibiotics, to protect the index patient and their sexual partner from re-infection during treatment. This may mean advice to avoid sex, or to use condoms for intercourse, until all current sexual partners have completed treatment. This article discusses the effectiveness of condoms as re-infection protection during therapy of gonorrhoea and chlamydial infection. Indirect evidence from studies on primary prevention indicates that, although physically, condoms are impermeable to STI pathogens, the risk of failure depends on the experience of the user and the frequency of use. Health care workers may over-estimate the protective value of condoms in this situation. Patients should be made aware of the risk of infection present, even in experienced condom users, if they choose to continue protected sexual intercourse during therapy for acute bacterial STIs.