Post-exposure prophylaxis is used after which scenario?

• A. After a head concussion
• B. After operating on a diabetic patient
• C. After contacting a patient with scabies
• D. After a possible HIV exposure

Answer: (D)

Post-exposure prophylaxis is used after a possible HIV exposure to prevent infection by starting a short course of antiretroviral medications as soon as possible—ideally within 2 hours and no later than 72 hours after exposure—and continuing for 28 days, with baseline and follow-up HIV testing. This approach targets reducing the risk of HIV seroconversion after exposure and is not indicated for non-infectious injuries or other conditions like head concussion, ongoing surgical concerns, or scabies exposure, which are managed with different precautions or treatments.