You can only start a course of PEP by getting the drug on prescription. You can do this by attending a sexual health or GUM clinic. You can also get the medication at Accident and Emergency (A&E) departments of hospitals, although some people do report it is harder to get the drug outside of large towns and cities. The medication is expensive, so clinics or hospitals will only give it to you if they believe you are genuinely at risk. You will always be tested for HIV before the medication is prescribed.