Maintenance Therapy for Herpes
For immunocompetent patients with frequent recurrent genital herpes (≥6 recurrences per year), daily suppressive therapy with valacyclovir 500 mg once daily or acyclovir 400 mg twice daily is recommended, which reduces recurrence frequency by at least 75%. 1
Immunocompetent Patients
Standard Suppressive Regimens
For patients with frequent recurrences, the following regimens are effective:
- Valacyclovir 500 mg once daily - preferred for convenience and proven efficacy 2
- Acyclovir 400 mg twice daily - equally effective alternative 1
- Acyclovir 200 mg 3-5 times daily - alternative regimen to identify the lowest effective dose 1
- Famciclovir 250 mg twice daily - comparable efficacy to acyclovir 1
Key Clinical Considerations
Suppressive therapy reduces recurrence frequency by >75% among patients with frequent recurrences but does not eliminate asymptomatic viral shedding or completely prevent transmission. 1
After 1 year of continuous suppressive therapy, discontinuation should be considered to reassess the patient's recurrence rate, as frequency often decreases over time. 1
Safety and efficacy have been documented for acyclovir use for up to 5-6 years, and for valacyclovir and famciclovir for at least 1 year. 1
Transmission Reduction
For HSV-2 seropositive patients in discordant heterosexual relationships, valacyclovir 500 mg once daily reduces transmission of symptomatic genital herpes by 75% and overall HSV-2 acquisition by 48%. 3, 4
HIV-Infected/Immunocompromised Patients
Modified Dosing Requirements
HIV-infected patients require higher doses and twice-daily regimens for effective suppression:
- Valacyclovir 500 mg twice daily (NOT once daily) - recommended dose for HIV-infected persons 1
- Acyclovir 400 mg 3-5 times daily - alternative for immunocompromised patients 1
- Famciclovir 500 mg twice daily - effective for reducing recurrences and subclinical shedding 1
Critical Safety Warning
Valacyclovir at doses of 8 g per day has been associated with thrombotic thrombocytopenic purpura/hemolytic uremic syndrome in immunocompromised patients, but standard treatment doses (≤1 g twice daily) are safe. 1
Daily suppressive therapy in HIV-infected persons decreases HIV concentration in plasma and genital secretions, though clinical benefit regarding HIV transmission remains uncertain. 1
Special Populations
Pregnancy
Routine suppressive therapy is not recommended during pregnancy for women with recurrent genital herpes, though acyclovir near term may reduce cesarean delivery rates by decreasing active lesions at delivery. 1
For pregnant women with frequent, severe recurrences, acyclovir prophylaxis may be indicated, as no pattern of adverse pregnancy outcomes has been reported after acyclovir exposure. 1
Genital HSV-1 Infection
Suppressive therapy is recommended only for patients with genital HSV-1 who have frequent recurrences, as HSV-1 recurs less frequently than HSV-2. 1
Acyclovir Resistance
Recognition and Management
Resistance should be suspected if lesions persist or do not begin to resolve within 7-10 days of therapy initiation. 1
Acyclovir-resistant strains are cross-resistant to valacyclovir and most are resistant to famciclovir. 1
For proven or suspected acyclovir-resistant HSV:
- Foscarnet 40 mg/kg IV every 8 hours until clinical resolution - first-line for resistant cases 1
- Topical cidofovir gel 1% applied daily for 5 consecutive days - alternative for external lesions 1
Acyclovir-resistant strains have been isolated from patients on suppressive therapy but have not been associated with treatment failure in immunocompetent patients. 1
Monitoring
No laboratory monitoring is required for patients receiving episodic or suppressive therapy unless substantial renal impairment exists. 1
Common adverse events (headache, nausea, nasopharyngitis) occur infrequently and are comparable across all antiviral agents. 1, 4