In a man in his 40s with a 2‑day history of uncomfortable, raised erythematous papules on the glans (corona) and distal third of the penile shaft, without vesicles or ulcers, what is the appropriate treatment?

Empiric Treatment for Suspected First-Episode Genital Herpes

This patient should be started on oral antiviral therapy for presumed first-episode genital herpes with acyclovir 400 mg three times daily for 7-10 days, valacyclovir 1 g twice daily for 7-10 days, or famciclovir 250 mg three times daily for 7-10 days 1.

Clinical Reasoning

The presentation of uncomfortable, raised erythematous papules on the corona and distal penile shaft in a 40s male over 2 days is most consistent with early first-episode genital herpes before classic vesiculation has occurred. The maculopapular appearance without vesicles yet is typical of the early papular stage that precedes vesicle formation in HSV infection.

Key Diagnostic Considerations

While the differential includes:

• Genital HSV (most likely given acute 2-day onset, location, and discomfort)
• Pearly penile papules (but these are chronic, asymptomatic, and uniformly dome-shaped around the corona) 2
• Angiokeratomas (typically purple/red/blue, often asymptomatic, and not acutely appearing) 3
• Inflammatory dermatoses like psoriasis or lichen planus (usually more chronic presentation) 4

The acute 2-day timeline with discomfort strongly favors HSV over benign anatomic variants or chronic inflammatory conditions.

Treatment Algorithm

Immediate Management (Day 1)

1. Start antiviral therapy immediately - do not wait for laboratory confirmation, as early treatment (within first 1-2 days) provides maximum benefit 1

2. Obtain diagnostic confirmation:

   • Swab lesions for HSV PCR (most sensitive) or viral culture
   • Request HSV type-specific testing (HSV-1 vs HSV-2 has prognostic implications for recurrence rates) 1, 5

3. Recommended first-line regimens 1:

   • Acyclovir 400 mg PO TID for 7-10 days, OR
   • Acyclovir 200 mg PO 5 times daily for 7-10 days, OR
   • Famciclovir 250 mg PO TID for 7-10 days, OR
   • Valacyclovir 1 g PO BID for 7-10 days

Valacyclovir or famciclovir offer easier dosing schedules (twice vs. three times daily) which may improve adherence 1.

Critical Counseling Points

Even before diagnostic confirmation, counsel the patient on 1:

• Abstain from sexual activity until lesions completely heal
• Natural history: This is likely a recurrent viral infection with potential for future episodes
• Asymptomatic viral shedding occurs and can transmit infection even without visible lesions
• Condom use with all future partners
• Inform current/recent sexual partners who need evaluation
• If HSV-2 confirmed, expect more frequent recurrences than HSV-1 genital infection 1

Follow-Up Strategy

• Extend therapy beyond 10 days if healing incomplete at day 10 1
• Once diagnosis confirmed and acute episode resolves, discuss:
  • Episodic therapy for future recurrences (if infrequent)
  • Suppressive daily therapy if ≥6 recurrences per year (reduces frequency by ≥75%) 1

Common Pitfalls to Avoid

1. Waiting for vesicles to appear - HSV lesions evolve from papules to vesicles to ulcers; early papular stage is still HSV and benefits most from immediate treatment

2. Delaying treatment for test results - Clinical diagnosis of first-episode genital herpes warrants immediate empiric therapy; laboratory confirmation guides counseling but shouldn't delay treatment 1, 5

3. Assuming benign anatomic variants - Pearly penile papules are chronic, uniform, asymptomatic, and don't appear acutely over 2 days 2

4. Using topical acyclovir - Substantially less effective than oral therapy and should not be used 1

5. Inadequate partner notification - Sexual contacts within the preceding weeks need evaluation regardless of symptoms 1

If Diagnosis Remains Uncertain

If lesions don't evolve as expected or PCR/culture returns negative, consider biopsy to exclude inflammatory dermatoses (lichen planus, psoriasis) or premalignant conditions, particularly if lesions persist beyond 2-3 weeks 4, 6. However, the acute presentation makes HSV by far the most likely diagnosis requiring immediate antiviral therapy.