What is the recommended oral therapy for a female patient with active vulvar lesions and a new diagnosis of Herpes Simplex Virus type 2 (HSV-2), and does she require chronic therapy?

Treatment of First-Episode HSV-2 Genital Herpes

For a patient with active vulvar lesions and a new diagnosis of HSV-2, the recommended first-line oral therapy is valacyclovir 1 g twice daily for 7-10 days, and she should be offered chronic suppressive therapy if she experiences ≥6 recurrences per year. 1

Initial Episode Treatment Regimens

The Centers for Disease Control and Prevention recommends several equally effective oral antiviral options for first-episode genital HSV-2 infection 1:

• Valacyclovir 1 g orally twice daily for 7-10 days (preferred for convenience) 1
• Acyclovir 400 mg orally three times daily for 7-10 days 1
• Acyclovir 200 mg orally five times daily for 7-10 days 1
• Famciclovir 250 mg orally three times daily for 7-10 days 1

Treatment may be extended beyond 10 days if healing is incomplete, which is particularly important for severe initial presentations 1. Valacyclovir offers superior convenience with twice-daily dosing compared to acyclovir's five-times-daily regimen, while maintaining equivalent efficacy 2.

Indications for Chronic Suppressive Therapy

Daily suppressive therapy is recommended for patients experiencing ≥6 recurrences per year 3, 1. This threshold is critical because:

• Suppressive therapy reduces recurrence frequency by ≥75% 3, 1
• HSV-2 causes more frequent recurrences than HSV-1, with most patients experiencing multiple episodes in the first year after infection 1, 4
• Asymptomatic viral shedding occurs more frequently with HSV-2 and in the first 12 months after infection 1

Suppressive Therapy Regimens

The Centers for Disease Control and Prevention recommends the following daily suppressive options 1:

• Valacyclovir 500 mg orally once daily (most convenient) 3, 1
• Valacyclovir 1 g orally once daily 3, 1
• Acyclovir 400 mg orally twice daily 3, 1
• Famciclovir 250 mg orally twice daily 3, 1

Note that valacyclovir 500 mg once daily may be less effective in patients with very frequent recurrences (≥10 episodes per year), in which case higher doses should be considered 5.

Early Initiation Strategy

For newly diagnosed patients, initiating suppressive therapy shortly after diagnosis is a valid strategy, even before establishing a recurrence pattern 4. A large randomized trial demonstrated that valacyclovir 1 g once daily started within 3 months of diagnosis kept 71% of patients recurrence-free at 24 weeks compared to 43% on placebo 4.

Duration and Reassessment

• Safety and efficacy have been documented for acyclovir suppressive therapy for up to 6 years and for valacyclovir for 1 year 1
• After 1 year of continuous suppressive therapy, consider discontinuation to reassess recurrence frequency, as some patients experience decreased recurrence rates over time 3, 1

Critical Patient Counseling Points

The Centers for Disease Control and Prevention emphasizes that patients must understand 1:

• HSV-2 is a chronic, incurable infection with potential for lifelong recurrence 1
• Antiviral medications control symptoms but do not eradicate the virus or prevent all recurrences 3, 1
• Asymptomatic viral shedding can occur, allowing transmission even without visible lesions 3, 1
• Patients should abstain from sexual activity when lesions or prodromal symptoms are present 3, 1
• Condoms should be used during all sexual exposures with new or uninfected partners 1
• Sexual partners should be informed about the HSV-2 diagnosis 1
• Women of childbearing age must inform healthcare providers about HSV-2 infection if they become pregnant, due to risk of neonatal transmission 1

Episodic Treatment for Future Recurrences

Patients should receive a prescription for antiviral medication to self-initiate at the first sign of recurrence 5, 1. For recurrent episodes, shorter 5-day courses are effective 3:

• Valacyclovir 500 mg orally twice daily for 5 days 3
• Acyclovir 400 mg orally three times daily for 5 days 3
• Famciclovir 125 mg orally twice daily for 5 days 3

Treatment is most effective when started during the prodromal period or within 24 hours of lesion onset 5, 1. There are no data supporting efficacy when treatment is initiated more than 24 hours after symptom onset for recurrent episodes 6.

Common Pitfalls to Avoid

• Never use topical acyclovir alone, as it is substantially less effective than oral therapy 5, 3, 1
• Do not use short-course therapy (1-3 days) in HIV-infected patients 7
• Suspect acyclovir resistance if lesions do not begin to resolve within 7-10 days of therapy, particularly in immunocompromised patients 7, 3