What is the role of post-exposure prophylaxis (PEP) in preventing sexually transmitted infections (STIs), including Human Immunodeficiency Virus (HIV), in a rape victim?

Post-Exposure Prophylaxis After Rape

HIV post-exposure prophylaxis (nPEP) should be offered to all rape survivors within 72 hours of assault (ideally within 24 hours) and continued for 28 days, as this intervention can reduce HIV transmission risk by approximately 81% based on occupational exposure data. 1

Immediate Assessment and Initiation

Risk Assessment

When evaluating a rape survivor for nPEP, assess the following factors to determine HIV transmission risk: 1

• Type of penetration: Vaginal or anal penetration carries higher risk than oral exposure 1
• Ejaculation on mucous membranes: Presence of semen increases transmission risk 1
• Multiple assailants: Increases cumulative exposure risk 1
• Mucosal trauma or bleeding: Genital lacerations (documented in 40-53% of assault cases) significantly increase transmission risk 1
• Assailant characteristics: Known HIV-positive status, MSM, injection drug use 1
• Local HIV epidemiology: Consider regional HIV prevalence 1

Testing Before Initiation

• Perform rapid HIV testing or combination antigen/antibody test on the survivor before starting nPEP, but do not delay the first dose while waiting for results 1, 2
• Baseline complete blood count and serum chemistry should be obtained 1
• Test the assailant for HIV whenever possible 1

Timing is Critical

• Start nPEP as soon as possible, ideally within 24 hours 1, 2
• nPEP can be initiated up to 72 hours post-assault, though efficacy decreases with time 1
• Evidence from South Africa showed that one woman who started nPEP at 96 hours still seroconverted, emphasizing the importance of early initiation 1

Recommended nPEP Regimens

Preferred Regimens for Adults and Adolescents

The CDC 2025 guidelines recommend: 1, 2

• Bictegravir/emtricitabine/tenofovir alafenamide (single tablet daily), OR
• Dolutegravir plus (tenofovir alafenamide OR tenofovir disoproxil fumarate) plus (emtricitabina OR lamivudine) 2

All regimens must be three-drug combinations continued for 28 days 1, 2

Initial Prescribing Strategy

For survivors experiencing acute distress who may struggle with decision-making: 1

• Provide a 3-5 day starter pack of nPEP 1
• Schedule follow-up within 3-7 days to provide remaining medication without interruption 1
• This approach allows time for additional counseling while maintaining treatment continuity 1

Comprehensive STI Prophylaxis

Beyond HIV, rape survivors require empirical treatment for other sexually transmitted infections: 1, 3

• Chlamydia and gonorrhea prophylaxis 1, 3
• Trichomoniasis treatment 3
• Hepatitis B vaccination (initiate or complete series) 3
• HPV vaccination (initiate or complete series) 3
• Emergency contraception within 120 hours for women of reproductive age 1, 3

Follow-Up Protocol

HIV Testing Schedule

Repeat HIV testing at: 1

• 6 weeks post-assault
• 3 months post-assault
• 6 months post-assault

Use methods capable of detecting acute HIV infection 1

Clinical Monitoring

• 24-hour follow-up visit with medical provider 2
• 3-7 day visit to assess medication tolerance and provide remaining nPEP supply 1
• 4-6 week visit for laboratory monitoring and clinical assessment 2
• 12-week visit for continued monitoring 2

Critical Counseling Points

Information to Discuss with Survivors

When offering nPEP, address: 1

1. Early initiation maximizes benefit (as soon as possible, up to 72 hours) 1, 2
2. Importance of adherence to daily dosing for full 28 days 1, 2
3. Close follow-up is essential 1
4. Severe adverse effects are rare from nPEP 1
5. Side effects may occur but are generally manageable 2

Addressing Adherence Challenges

Common pitfall: Only 40% of sexual assault survivors complete the full 28-day nPEP course, with adherence rates significantly lower than other PEP populations. 1, 4

Barriers to completion include: 4

• Medication side effects
• Forgetting doses
• Stigma and self-blame
• Mental health problems (depression, PTSD)
• Poor understanding of HIV risk

Strategies to improve adherence: 1, 4

• Provide supportive services through sexual assault crisis centers 1
• Offer "one-stop" services with HIV testing and nPEP at initial consultation 4
• Arrange family/peer support for medication reminders 4
• Provide monetary support for transportation to follow-up visits 4
• Ensure access to counseling services 4

Special Populations

Pregnant or Breastfeeding Women

• Offer nPEP when indicated 1
• Consult with specialists for ARV selection during pregnancy 1
• Provide evidence-based counseling about continuing versus interrupting breastfeeding during nPEP 1
• Contact NCCC PEPline at 888-448-4911 for expert consultation 1

Children and Adolescents

• Assess immediate safety before discharge 1, 3
• Contact child protective services and law enforcement if imminent risk exists 1
• Child should remain under medical supervision until authorities establish a care plan 1
• Adapt dosing based on weight and age 1

Coordination of Care

Forensic Examination

• Consult sexual assault forensic or nurse examiner when available 1
• Instruct patient not to change clothes, bathe, eat, drink, urinate, defecate, or douche before examination if possible 1
• If patient has already done these activities, still encourage forensic examination 1
• Refer to emergency department or sexual assault treatment center for comprehensive evaluation 1

Financial Coverage

• All states provide reimbursement for medical expenses after sexual assault through the U.S. Department of Justice Victim's Compensation Program when assault is reported to police 1, 3
• Some localities have special programs covering ARV medications with specific reporting requirements 1

Transition to PrEP

For survivors with ongoing HIV exposure risk after completing nPEP: 1, 2

• Discuss HIV pre-exposure prophylaxis (PrEP) before completing the 28-day nPEP course 1, 2
• Create a transition plan from nPEP to PrEP without interruption 1, 2
• This is particularly important for survivors who may have continued risk from intimate partner violence or other circumstances 1

Evidence Base

The recommendation for nPEP after sexual assault is extrapolated from occupational exposure data showing 81% risk reduction with zidovudine monotherapy in healthcare workers. 1 While no randomized controlled trials exist for sexual assault specifically, observational studies support efficacy: 1

• In São Paulo, Brazil: 0/180 treated survivors seroconverted versus 4/145 (2.7%) untreated survivors 1
• In San Francisco: 0 seroconversions among 401 persons receiving nPEP for sexual exposures 1
• In British Columbia: 0 seroconversions among 590 persons completing nPEP 1

The absence of randomized trials does not diminish the recommendation strength, as the potential benefit clearly outweighs risks given the catastrophic outcome of HIV infection and the low incidence of severe adverse effects from modern ARV regimens. 1