What is the recommended treatment for a first genital herpes outbreak in an otherwise healthy adult?

Management of Initial Genital Herpes Outbreak

For a first episode of genital herpes in an otherwise healthy adult, start oral valacyclovir 1 gram twice daily for 7-10 days, which is the CDC's current first-line recommendation. 1

First-Line Treatment Regimens

The CDC recommends several oral antiviral options for initial genital herpes, all with comparable efficacy: 1, 2

• Valacyclovir 1 gram orally twice daily for 7-10 days (preferred for convenience and bioavailability) 1, 2
• Acyclovir 400 mg orally three times daily for 7-10 days 1, 2
• Acyclovir 200 mg orally five times daily for 7-10 days 3, 2
• Famciclovir 250 mg orally three times daily for 7-10 days 2

Extend treatment beyond 10 days if healing remains incomplete, as initial episodes can be prolonged and severe. 1, 2

Why Oral Systemic Therapy is Essential

Avoid topical acyclovir—it is substantially less effective than oral therapy and does not improve systemic symptoms. 3, 1, 2 Topical formulations fail to address viremia, lymphadenopathy, constitutional symptoms, or viral shedding from multiple sites (cervix, urethra, pharynx). 4, 5

Oral antivirals reduce: 5

• Duration of viral shedding (median 2-3 days vs. 13 days with placebo) 4
• Time to lesion healing (shortened by approximately 12 days) 4
• Severity and duration of pain, dysuria, and constitutional symptoms (by 3-5 days) 5
• Risk of complications such as urinary retention, aseptic meningitis, and disseminated disease 4

Severe Disease Requiring Hospitalization

For patients with disseminated infection, encephalitis, pneumonitis, hepatitis, or inability to tolerate oral medications, administer acyclovir 5-10 mg/kg IV every 8 hours for 5-7 days or until clinical resolution. 3, 2

Indications for IV therapy include: 3

• Central nervous system involvement
• Visceral organ involvement
• Extensive mucocutaneous disease preventing oral intake
• Immunocompromised status with severe presentation

Special Considerations for Herpes Proctitis

For first-episode herpes proctitis, use acyclovir 400 mg orally five times daily for 10 days, as rectal HSV infection requires higher dosing due to increased viral replication at this site. 3

Critical Patient Counseling Points

Patients must understand the following at the initial visit: 3, 2

• Genital herpes is a chronic, incurable infection with potential for lifelong recurrence. 3, 2
• Asymptomatic viral shedding occurs even without visible lesions, enabling transmission to partners. 3, 2
• Abstain from all sexual activity when lesions or prodromal symptoms are present. 3, 2
• Use condoms during all sexual exposures with new or uninfected partners, though condoms do not eliminate transmission risk completely. 3, 2
• Inform all sexual partners about the HSV infection. 2
• The risk of neonatal transmission is 25-44% if primary infection occurs at delivery; women of childbearing age must inform obstetric providers. 2

Provide a Prescription for Future Recurrences

At the initial visit, give patients a prescription for episodic therapy to self-initiate at the first sign of recurrence (prodrome or within 24 hours of lesion onset). 1, 2 Early treatment during the prodrome is critical, as peak viral replication occurs in the first 24 hours. 1

Recommended episodic regimens for recurrences: 1, 2

• Valacyclovir 500 mg orally twice daily for 5 days 2
• Acyclovir 800 mg orally twice daily for 5 days 2
• Famciclovir 125 mg orally twice daily for 5 days 2

When to Consider Suppressive Therapy

Discuss daily suppressive therapy if the patient experiences ≥6 recurrences per year, which reduces recurrence frequency by ≥75%. 1, 2, 6 Suppressive options include: 2, 6

• Valacyclovir 1 gram orally once daily (most effective for ≥10 recurrences/year) 6
• Valacyclovir 500 mg orally once daily (for <10 recurrences/year) 6
• Acyclovir 400 mg orally twice daily (safety documented up to 6 years) 2, 6

After 1 year of continuous suppressive therapy, discontinue temporarily to reassess recurrence frequency, as natural decline often occurs over time. 2, 6

Common Pitfalls to Avoid

• Do not delay treatment—initiate antivirals as soon as the diagnosis is suspected, ideally within 72 hours of symptom onset. 7
• Do not use topical acyclovir as monotherapy—it provides no benefit for systemic symptoms or viral shedding from non-cutaneous sites. 3, 1, 2
• Do not assume HSV-2—HSV-1 causes 5-30% of first-episode genital herpes and has a much lower recurrence rate; type-specific serology has prognostic value. 2
• Do not forget renal function assessment—adjust antiviral dosing based on creatinine clearance to avoid nephrotoxicity. 2