When should PEP be started after exposure?

When should PEP be started after exposure?

• A. Within 24 hours
• B. Within 1 week
• C. Within 2 weeks
• D. Within 72 hours

Answer: (D)

The timing of PEP matters because its effectiveness hinges on interrupting the virus before it establishes infection. PEP works best when started as soon as possible after exposure, with a recommended window up to 72 hours. The chance of preventing HIV decreases the longer you wait, and after 72 hours the benefit is not considered reliable in standard guidelines. So, starting PEP within 72 hours offers the best opportunity to prevent infection following exposure. If exposure is suspected, seek evaluation immediately; if within the window, initiate a 28-day antiretroviral regimen and arrange follow-up HIV testing.

The timing of PEP matters because its effectiveness hinges on interrupting the virus before it establishes infection. PEP works best when started as soon as possible after exposure, with a recommended window up to 72 hours. The chance of preventing HIV decreases the longer you wait, and after 72 hours the benefit is not considered reliable in standard guidelines. So, starting PEP within 72 hours offers the best opportunity to prevent infection following exposure. If exposure is suspected, seek evaluation immediately; if within the window, initiate a 28-day antiretroviral regimen and arrange follow-up HIV testing.