What is the recommended post‑exposure prophylaxis (PEP) regimen for HIV after a needle‑prick injury, including the specific drugs, dosages, duration, and follow‑up HIV testing schedule?

HIV Post-Exposure Prophylaxis After Needle Prick Injury

Start a 3-drug antiretroviral regimen within 72 hours (ideally within 24 hours) of needle-stick injury, continue for 28 days, and perform HIV testing at baseline, 4-6 weeks, and 12 weeks post-exposure.

Immediate Actions

When a needle-stick injury occurs, immediately wash the wound with soap and water. Do not delay—time is critical. The effectiveness of PEP decreases significantly after 72 hours, and every hour counts 1.

When to Start PEP

Initiate PEP if:

• The exposure occurred within the past 72 hours
• The source patient has HIV without sustained viral suppression, OR their HIV status is unknown
• The exposure presents substantial transmission risk (percutaneous injury with blood or visibly bloody fluid) 1

Do NOT start PEP if:

• The source is confirmed HIV-negative
• More than 72 hours have elapsed since exposure
• The source has documented sustained viral suppression (undetectable viral load)

Preferred Drug Regimens

The most current 2025 CDC guidelines recommend two preferred 3-drug regimens for adults 1:

Option 1 (Single-pill regimen):

• Bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) - one tablet daily

Option 2:

• Dolutegravir (DTG) PLUS
• (Tenofovir alafenamide [TAF] OR tenofovir disoproxil fumarate [TDF]) PLUS
• (Emtricitabine [FTC] OR lamivudine [3TC])

These newer integrase inhibitor-based regimens have replaced older protease inhibitor regimens due to better tolerability and simpler dosing, which improves completion rates 2, 1.

Duration

Exactly 28 days of continuous treatment 2, 1. Provide the full 28-day prescription at the initial visit rather than "starter packs"—this significantly improves completion rates 2.

HIV Testing Schedule

Baseline (before starting PEP):

• Rapid HIV test AND/OR laboratory-based antigen/antibody (Ag/Ab) combination test
• If the exposed person used long-acting injectable PrEP in the past 12 months, also add HIV nucleic acid test (NAT) 1

Interim testing at 4-6 weeks:

• Laboratory-based HIV Ag/Ab test PLUS diagnostic HIV NAT
• May be deferred if PEP started within 24 hours AND no doses were missed 1

Final testing at 12 weeks:

• Laboratory-based HIV Ag/Ab combination immunoassay PLUS diagnostic HIV NAT 1

This updated 2025 testing schedule differs from older guidelines that recommended testing out to 6 months. The 12-week endpoint with combination Ag/Ab plus NAT testing provides adequate detection while using more sensitive modern assays 1.

Critical Follow-Up Points

Within 72 hours of starting PEP:

• Assess for drug toxicity and side effects
• Provide adherence counseling—completion of the full 28 days is essential 1

At 2 weeks:

• Monitor for drug toxicity
• Address any side effects that might compromise adherence

Common side effects include nausea and diarrhea, which can often be managed with antiemetics and antimotility agents without changing the regimen 3. Do not let manageable side effects derail completion.

Important Caveats

Assess the source patient when possible:

• Test source for HIV antibody using rapid testing if available
• If source is confirmed HIV-negative at any point, stop PEP immediately 1

Pregnancy considerations:

• PEP is still recommended in pregnancy
• Regimen selection may need modification based on trimester and drug safety profiles

Drug interactions:

• Complete a clinical assessment for comorbidities, current medications, and allergies before prescribing
• Integrase inhibitors have fewer drug interactions than older protease inhibitor regimens 1

Resistance concerns:

• If the source patient is known to have drug-resistant HIV, consult an HIV specialist immediately
• The National Clinician Consultation Center PEPline is available at 888-448-4911 1

Transition to PrEP

If the exposed person has ongoing HIV exposure risk (e.g., healthcare worker with repeated occupational exposures), consider immediate transition from PEP to pre-exposure prophylaxis (PrEP) after completing the 28-day course and confirming negative HIV testing 1.

The shift from older 2-drug regimens to universal 3-drug regimens reflects both the availability of better-tolerated medications and the difficulty in accurately assessing resistance risk in real-world settings 2. While the 2001 guidelines offered 2-drug "basic regimens" 3, current evidence supports 3-drug therapy for all exposures to maximize prevention efficacy.