APA Dictionary of Psychology

an ongoing preventive strategy in which antiretroviral medication is taken before potential exposure to human immunodeficienty virus (HIV) to prevent infection in HIV-negative individuals, particularly those with a higher ongoing risk, such as individuals with an HIV-positive partner, multiple partners, or injectable drug use. PrEP medications can be taken as a daily oral drug or long-acting injectable, and maintain drug levels in the bloodstream sufficient to prevent HIV from replicating if exposure occurs. A common clinical pathway is the use of post-exposure prophylaxis after a potential exposure occurs, and then a transition to PrEP once a sustained HIV risk is identified.