What prophylactic measures should a male take after potential STD exposure?

Post-Exposure STD Prophylaxis for Males

Males with potential STD exposure should receive immediate empiric antimicrobial prophylaxis covering gonorrhea, chlamydia, and trichomonas, along with hepatitis B vaccination if unvaccinated, followed by comprehensive testing at baseline, 2 weeks, and 3 months. 1

Immediate Prophylactic Treatment (Within 72 Hours)

Administer empiric antimicrobial therapy immediately without waiting for test results, as follow-up compliance is often poor and early treatment prevents complications: 1

• Ceftriaxone 125 mg IM single dose (covers gonorrhea) 1
• PLUS Doxycycline 100 mg orally twice daily for 7 days (covers chlamydia and early syphilis) 1
• PLUS Metronidazole 2 g orally single dose (covers trichomonas and bacterial vaginosis) 1

Doxycycline Post-Exposure Prophylaxis (DoxyPEP)

• For men who have sex with men specifically: Doxycycline 200 mg within 72 hours of condomless sex is now recommended as part of comprehensive STI care 2
• This window closes after 72 hours, making immediate presentation critical 2

Vaccination

Hepatitis B vaccination should be initiated immediately if the patient is unvaccinated, as HBV is frequently sexually transmitted: 1

• Complete the full 3-dose series (0,1-2 months, 6 months) 1
• Hepatitis A vaccination is also recommended for men who have sex with men 1

Comprehensive Testing Schedule

Baseline Testing (Immediate)

Perform comprehensive screening even if prophylaxis is given, as baseline results guide follow-up: 2

• Gonorrhea and chlamydia NAATs from all exposure sites (urethra/urine, rectum if receptive anal exposure, pharynx if receptive oral exposure) 2
• Syphilis serologic testing (both nontreponemal RPR/VDRL and treponemal tests) 2
• HIV testing (laboratory-based Ag/Ab test) 2
• Hepatitis B serologic testing if vaccination status unknown 2

Critical pitfall: Testing only genital sites misses substantial infections, particularly pharyngeal and rectal gonorrhea in men who have sex with men 2

2-Week Follow-Up Testing

Repeat bacterial STI testing at 2 weeks if initial tests were negative and prophylaxis was not given, as infectious agents may not have reached detectable concentrations initially: 1, 3

• Gonorrhea and chlamydia NAATs from exposure sites 3
• This addresses the bacterial STI window period 3

3-Month Follow-Up Testing (Definitive)

This is mandatory and cannot be skipped, as it captures infections missed by earlier testing: 2, 3

• HIV testing (4-6 weeks minimum, but 12 weeks is definitive for ruling out infection) 2
• Syphilis serologic testing (6-12 week window period) 2, 3
• Retest for gonorrhea and chlamydia if initially positive and treated (high reinfection rates of 25% within 3.6 months for chlamydia) 2

Risk Reduction Counseling

Provide specific behavioral guidance: 1

• Abstain from sexual activity until 7 days after completing prophylactic treatment 1
• Use condoms consistently and correctly for all future sexual encounters (new condom for each act, water-based lubricants only, hold base during withdrawal) 1
• Both partners should be tested before initiating sexual activity with new partners 1

Important caveat: Condoms are highly effective for mucosal transmission (HIV, gonorrhea, chlamydia) but less protective against skin-to-skin transmission (HPV, HSV, syphilis chancres) 1

Ongoing Screening for High-Risk Individuals

If the patient has ongoing high-risk behaviors (multiple partners, anonymous partners, substance use during sex, commercial sex work involvement), recommend screening every 3-6 months indefinitely: 2

• Studies show 20% chlamydia and 17% gonorrhea positivity with frequent screening in high-risk populations 2
• This applies regardless of reported condom use, as protection is incomplete 2

Partner Management

All sexual partners within the preceding 60 days must be evaluated and treated, even if asymptomatic: 1

• Partners should receive the same empiric prophylactic regimen 1
• Expedited partner therapy may be appropriate depending on local regulations 1

Common Pitfalls to Avoid

• Testing too early and stopping there: A negative test at 1 week does not rule out infection 2
• Failing to test exposure-specific sites: Pharyngeal and rectal testing is essential based on sexual practices 2
• Skipping the 3-month follow-up: This is when HIV and syphilis become definitively detectable 2, 3
• Accepting patient reassurance about condom use: Even with reported consistent use, screening remains essential 2
• Not vaccinating against hepatitis B: This is a missed opportunity for highly effective prevention 1