At what frequency of Herpes Simplex Virus 2 (HSV2) episodes is suppressive therapy typically recommended?

Suppressive Therapy for HSV-2: Recommended Episode Threshold

Daily suppressive therapy should be initiated when patients experience 6 or more recurrent HSV-2 episodes per year. 1, 2

Primary Indication for Suppressive Therapy

• The CDC establishes ≥6 recurrences per year as the threshold for recommending daily suppressive therapy in patients with genital HSV-2 infection 1, 2
• This frequency-based criterion is the cornerstone for determining which patients will benefit most from transitioning from episodic to suppressive management 2

Benefits of Suppressive Therapy at This Threshold

• Suppressive therapy reduces recurrence frequency by ≥75% in patients meeting the ≥6 episodes/year criterion 1, 2, 3
• Reduces asymptomatic viral shedding, though does not eliminate it completely 1, 2
• Improves quality of life by preventing physical discomfort, psychological distress, and social impact of recurrent outbreaks 2
• Clinical trial data demonstrate that 39% of patients remain recurrence-free at 6 months and 29% at 12 months on suppressive therapy, compared to only 10% and 6% on placebo, respectively 4

Recommended Suppressive Regimens

For patients with <10 recurrences per year:

• Valacyclovir 500 mg once daily 1, 2
• Acyclovir 400 mg twice daily 1, 2
• Famciclovir 250 mg twice daily 1, 2

For patients with ≥10 recurrences per year:

• Valacyclovir 1,000 mg once daily provides better suppression than the 500 mg dose 2
• The 500 mg once-daily valacyclovir regimen appears less effective in this higher-frequency subgroup 3

Duration and Reassessment

• Long-term safety is well-established: acyclovir for up to 6 years and valacyclovir/famciclovir for at least 1 year of continuous use 1, 2, 3
• After 1 year of continuous suppressive therapy, discontinuation should be discussed to reassess the patient's current recurrence rate and psychological adjustment 1, 2, 3
• Recurrence frequency often decreases over time, making periodic reassessment essential 3

Special Populations

HIV-infected patients:

• Require higher doses: valacyclovir 500 mg twice daily (not once daily) for suppressive therapy 2, 3
• Prolonged or severe episodes are more common in this population 2

Critical Safety Considerations

• No laboratory monitoring is needed unless substantial renal impairment exists 2, 3
• Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome has been reported with high-dose valacyclovir (8 g/day) but not at suppressive therapy doses 2, 3
• Acyclovir resistance is rare in immunocompetent patients but should be suspected if lesions do not resolve within 7-10 days of therapy 2, 3

Common Pitfalls to Avoid

• Do not prescribe valacyclovir 500 mg once daily for HIV-infected patients—they require 500 mg twice daily 2
• Avoid topical acyclovir, which has substantially lower effectiveness compared to oral therapy 1
• Counsel patients that suppressive therapy does not eliminate asymptomatic viral shedding or completely prevent transmission 1, 2, 3
• Patients must understand that the virus is not eradicated and recurrences may still occur, albeit at significantly reduced frequency 1