What is an important counseling point regarding Pre-Exposure Prophylaxis (PrEP) for Human Immunodeficiency Virus (HIV) prevention?

PrEP Counseling: Essential Points

The correct answer is B: PrEP is effective for the prevention of HIV, but it should be combined with other preventive measures to further reduce HIV and STI risk. This is the most accurate and clinically appropriate counseling point, as PrEP does not provide 100% protection against HIV, does not prevent other sexually transmitted infections, and must be delivered as part of a comprehensive prevention strategy 1, 2, 3.

Why the Other Options Are Incorrect

Option A is incorrect because PrEP does not prevent STIs—it only reduces HIV acquisition risk 2, 4, 5. Multiple guidelines explicitly state that PrEP does not protect against other sexually transmitted infections 1, 4.

Option C is incorrect because PrEP does not provide 100% protection against HIV, even with perfect adherence 2, 3. While adherence to daily dosing can achieve approximately 90-99% risk reduction, no prevention method offers absolute protection 1, 6.

Option D is incorrect because it confuses PrEP (pre-exposure prophylaxis) with PEP (post-exposure prophylaxis). PrEP is taken daily before potential exposures, while PEP is the intervention taken within 72 hours after a high-risk exposure 1.

Core Counseling Messages for PrEP

PrEP Must Be Part of Comprehensive Prevention

• PrEP should be delivered as part of a comprehensive set of prevention services, including risk-reduction counseling, PrEP medication adherence counseling, and ready access to condoms 1.
• Patients must understand that PrEP does not prevent other sexually transmitted infections and must be combined with comprehensive prevention services 2, 3, 4.
• Practice safer sex by using latex or polyurethane condoms to reduce the risk of getting STIs 4.

Adherence Is Critical for Efficacy

• The importance of adherence to daily medication and its influence on efficacy must be clearly discussed 1.
• Adherence to daily medication is the single most critical factor determining efficacy 3.
• Detection of tenofovir in plasma has been associated with approximately 90% reduction in HIV acquisition, while drug levels commensurate with daily use were associated with an estimated 99% reduction in HIV risk 1.
• Greater adherence was associated with greater efficacy, with relative risk of 0.27 (95% CI, 0.19-0.39) when adherence was ≥70% 6.

HIV Testing Requirements

• Patients must be confirmed HIV-negative before starting PrEP using an HIV antibody test, ideally a fourth-generation antigen-antibody assay 2, 3.
• HIV-1 resistance substitutions may emerge in individuals with undetected HIV-1 infection who are taking only PrEP, because it does not constitute a complete regimen for HIV-1 treatment 4.
• While using PrEP, HIV-1 testing should be repeated at least every 3 months, and upon diagnosis of any other STIs 4.
• Test for acute HIV infection if the patient has flu-like symptoms or reports unprotected sex with an HIV-positive person in the preceding month 2, 3.

STI Screening and Management

• Get tested for other sexually transmitted infections, such as syphilis, chlamydia, and gonorrhea, that may facilitate HIV-1 transmission 4.
• Sexually transmitted infection treatment should be provided when indicated by laboratory screening tests conducted at least every 6 months 1.
• PrEP use was associated with a significant increase in rectal chlamydia (OR, 1.59; 95% CI, 1.19-2.13) and any STI diagnosis (OR, 1.24; 95% CI, .99-1.54) 7.

Common Pitfalls to Avoid

• Never initiate PrEP without confirming HIV-negative status, as undetected HIV infection can lead to drug resistance 3, 4.
• Do not tell patients PrEP provides complete protection—even with perfect adherence, it is highly effective but not 100% protective 2, 3.
• Do not prescribe more than a 90-day supply; renewal should only occur after confirming continued HIV-negative status 1, 2, 3.
• Avoid prescribing TDF-based PrEP to patients with creatinine clearance <60 mL/min 1, 3.

Special Considerations

Pregnancy and Breastfeeding

• Determine pregnancy plans, current pregnancy status, and breastfeeding status at every visit for women of reproductive age 1, 2, 3.
• Safety data for infants exposed during pregnancy is incomplete, though no harm has been reported to date 1, 2, 3.
• Do not prescribe PrEP to women who are breastfeeding 1, 2, 3.

Renal and Bone Health

• Confirm that calculated creatinine clearance is ≥60 mL/min using the Cockcroft-Gault formula before prescribing TDF-based PrEP 1, 2.
• PrEP was associated with an increased risk of renal adverse events (RR, 1.43; 95% CI, 1.18-1.75), though most were mild and reversible 6.