What is the treatment for genital herpes caused by Herpes Simplex Virus (HSV)?

Treatment for Genital Herpes (HSV)

First Clinical Episode

For a first episode of genital herpes, initiate oral antiviral therapy immediately with one of the following CDC-recommended regimens for 7-10 days: valacyclovir 1 g twice daily, acyclovir 400 mg three times daily, acyclovir 200 mg five times daily, or famciclovir 250 mg three times daily. 1, 2, 3

• Treatment duration should be extended beyond 10 days if healing remains incomplete 1, 3
• Higher acyclovir dosages (400 mg five times daily) may be necessary for severe presentations, particularly in immunocompromised patients 1, 3
• Topical acyclovir is substantially less effective than oral therapy and should not be used 1, 2, 3

Clinical Context for First Episodes

• HSV-1 causes 5-30% of first-episode genital herpes cases, but recurrences are much less frequent compared to HSV-2 infection 1, 3
• Identifying the viral serotype (HSV-1 vs HSV-2) has prognostic importance for counseling about recurrence frequency 1, 3
• Some first episodes present with severe disease requiring hospitalization, warranting IV acyclovir 5-10 mg/kg every 8 hours for 5-7 days 3

Recurrent Episodes

For recurrent genital herpes, episodic therapy is most effective when initiated during prodrome or within 1 day of lesion onset, using valacyclovir 500 mg twice daily for 5 days as the preferred regimen. 2, 3

Alternative Episodic Regimens (all for 5 days):

• Acyclovir 400 mg three times daily 2, 3
• Acyclovir 800 mg twice daily 2, 3
• Acyclovir 200 mg five times daily 2, 3
• Famciclovir 125 mg twice daily 2, 3

Optimizing Episodic Treatment

• Provide patients with medication or prescription in advance to self-initiate at first sign of prodrome or lesions 3
• Starting treatment beyond 24 hours of symptom onset significantly reduces effectiveness 2, 3
• Valacyclovir demonstrates equivalent efficacy to acyclovir with simpler dosing (twice daily vs five times daily), which may improve adherence 4, 5, 6

Suppressive Therapy

For patients with frequent recurrences (≥6 episodes per year), daily suppressive therapy with valacyclovir 1 g once daily or 500 mg once daily is recommended, reducing recurrence frequency by ≥75%. 2, 3

Alternative Suppressive Regimens:

• Acyclovir 400 mg twice daily 2, 3
• Famciclovir 250 mg twice daily 2, 3

Duration and Monitoring

• Safety and efficacy documented for acyclovir up to 6 years and valacyclovir/famciclovir for 1 year 2, 3
• After 1 year of continuous suppressive therapy, consider discontinuation to reassess recurrence frequency 2, 3
• Suppressive therapy reduces asymptomatic viral shedding in addition to clinical recurrences 2, 3
• Valacyclovir 500 mg once daily has proven efficacy in placebo-controlled trials for patients with 9 or fewer recurrences per year 4

Special Populations

HIV-Infected Patients

• HIV-infected patients with recurrent genital herpes showed 65% recurrence-free rate at 6 months with valacyclovir 500 mg twice daily versus 26% with placebo 4
• Higher doses or longer treatment courses may be necessary, with closer monitoring for treatment failures 1

Pregnancy Considerations

• Routine suppressive therapy is not recommended during pregnancy for recurrent genital herpes 2
• Pregnant women with genital herpes must inform healthcare providers about HSV infection for neonatal transmission risk assessment 3
• The safety of systemic acyclovir and valacyclovir in pregnancy has not been definitively established 2

Antiviral Resistance

Suspect acyclovir resistance if lesions fail to begin resolving within 7-10 days of therapy; use foscarnet 40 mg/kg IV every 8 hours for proven or suspected resistance. 2

• Resistance remains rare in immunocompetent patients but occurs more frequently in immunocompromised individuals 3, 7
• Single-day famciclovir treatment does not increase development of penciclovir resistance 7

Critical Pitfalls to Avoid

• Never use topical acyclovir - it is substantially less effective than oral therapy 1, 2, 3
• Avoid valacyclovir 8 g/day - associated with hemolytic uremic syndrome/thrombotic thrombocytopenic purpura in immunocompromised patients 2
• Delaying episodic treatment beyond the prodrome or first day of lesions significantly reduces effectiveness 2, 3
• Failing to consider suppressive therapy in patients with ≥6 recurrences per year misses opportunity for 75% reduction in episodes 2, 3

Essential Patient Counseling

• Genital herpes is a recurrent, incurable viral disease; antivirals control symptoms but do not eradicate latent virus 1, 2, 3
• Abstain from sexual activity when lesions or prodromal symptoms are present 2, 3
• Inform all sex partners about having genital herpes 2, 3
• Use condoms during all sexual exposures with new or uninfected partners 2, 3
• Asymptomatic viral shedding can occur and lead to transmission, particularly with HSV-2 and within the first 12 months of infection 2, 3