If you've had unprotected sex within the last 72 hours and you're worried you may have been infected with HIV read on.....
PEP stands for "Post Exposure Prophylaxis". It's a treatment that may prevent HIV infection entering the body. For it to be effective, treatment has to start within 72 hours after sexual or needle-stick exposure to HIV. The treatment must be taken for a month, it can have unpleasant side effects, and does not guarantee a HIV negative result.
PEP is available from the GU/Sexual Health Clinic at Royal Cornwall Hospital (Treliske), it is also available out of hours from the Accident & Emergency Department. The sooner PEP treatment is started (after exposure to HIV) the better chance it has of preventing HIV infection.