Within 72 hours after unprotected intercourse; what is the best option for HIV post-exposure prophylaxis?

• A. Observation and testing later
• B. Vaccination against HIV
• C. Start HIV PEP with a 3-drug regimen as soon as possible and continue for 28 days
• D. A single antiretroviral for 7 days

Answer: (C)

After potential HIV exposure, the goal of post-exposure prophylaxis (PEP) is to prevent the virus from establishing infection by suppressing replication as quickly as possible. The benefit is greatest when PEP is started within 72 hours of exposure, and it is continued for 28 days. The standard approach uses a three-drug antiretroviral regimen, typically combining two nucleoside reverse transcriptase inhibitors with an integrase inhibitor. This three-drug course provides robust coverage to blunt any virus that may have entered the body, reducing the chance of seroconversion.

Vaccination against HIV does not exist, and simply observing and testing later does not prevent infection. A single antiretroviral pill would be insufficient to reliably prevent HIV after a high-risk exposure. Starting a full 28-day, three-drug PEP regimen as soon as possible offers the best protection in this scenario. After starting PEP, follow-up testing and monitoring for drug tolerance and potential side effects are important.