What Are PrEP and PEP? How Are They Different?

PrEP, or Pre-Exposure Prophylaxis, is a medication taken by people who are HIV-negative but at risk of exposure to HIV. It is taken in advance daily and consistently to prevent infection if exposed to the virus. PrEP is highly effective when taken correctly and is recommended for people who have multiple sexual partners, inconsistent condom use, or an HIV-positive partner.

PEP, or Post-Exposure Prophylaxis, is an emergency medication regimen used after potential exposure to HIV. This could happen through unprotected sex, sexual assault, or accidental exposure such as a needle-stick injury. PEP must be started within 72 hours of the exposure and is taken for 28 consecutive days to prevent the virus from taking hold in the body.

The Key Difference Between PrEP and PEP

The main difference is timing. PrEP is taken before possible exposure, while PEP is taken after a high-risk event has already happened. PrEP is used as a long-term, ongoing prevention strategy, whereas PEP is short-term and must be initiated as soon as possible ideally within hours after exposure. Both require strict adherence to dosing for maximum effectiveness.

Use the Right Medication for the Right Situation

Both PrEP and PEP are powerful tools in HIV prevention, but they serve different purposes. PrEP is best for people who are frequently at risk and want to take control of their long-term sexual health. PEP is a backup plan used in emergencies when exposure was unexpected. Choosing the right method depends on your situation, lifestyle, and level of risk.

Always Consult a Health Professional First

Before starting PrEP or PEP, it’s essential to talk to a healthcare provider or a sexual health clinic. They can assess your risk level, explain how the medications work, and provide proper follow-up care. Both medications require monitoring and professional guidance to ensure they’re being used safely and effectively for HIV prevention.