What is the treatment for Herpes Simplex Virus (HSV) 1 and 2?

Treatment for HSV-1 and HSV-2

For both HSV-1 and HSV-2 infections, oral antiviral therapy with valacyclovir, acyclovir, or famciclovir is the standard of care, with valacyclovir being preferred for most clinical scenarios due to its convenient dosing and proven efficacy. 1

First Clinical Episode Treatment

For initial genital herpes episodes, longer treatment courses of 7-10 days are required:

• Valacyclovir 1 g orally twice daily for 7-10 days (preferred regimen) 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 1, 2
• Famciclovir 250 mg orally three times daily for 7-10 days 1, 2

Treatment may be extended beyond 10 days if healing is incomplete 1, 2. For severe mucocutaneous HSV lesions, initiate IV acyclovir and switch to oral therapy once lesions begin to regress 3.

Recurrent Episodes Treatment

For recurrent outbreaks, shorter 5-day courses are effective:

• Valacyclovir 500 mg orally twice daily for 5 days (preferred for convenience) 1, 4, 5
• Acyclovir 400 mg orally three times daily for 5 days 1, 4
• Acyclovir 800 mg orally twice daily for 5 days 1, 4
• Famciclovir 125 mg orally twice daily for 5 days 1, 4

Timing is critical: Episodic therapy is most effective when started during the prodromal period or within 1 day after lesion onset 1, 4. Treatment delayed beyond 72 hours significantly reduces effectiveness 1, 4. Patients should be provided with medication or a prescription to initiate treatment at the first sign of prodrome 4.

Suppressive Therapy

For patients with frequent recurrences (≥6 episodes per year), daily suppressive therapy is recommended:

• Valacyclovir 1 g orally once daily (standard dose) 1, 4, 5
• Valacyclovir 500 mg orally once daily (alternative dose) 1, 5
• Acyclovir 400 mg orally twice daily 1, 4
• Famciclovir 250 mg orally twice daily 1

Suppressive therapy reduces recurrence frequency by ≥75% and reduces asymptomatic viral shedding 1, 4. After 1 year of continuous suppressive therapy, consider discontinuation to reassess recurrence frequency 1.

Transmission Prevention Benefit

Suppressive valacyclovir 500 mg once daily reduces HSV-2 transmission to susceptible heterosexual partners by approximately 50% 3, 6. In clinical trials, symptomatic HSV-2 acquisition occurred in 0.5% of partners whose source partners received valacyclovir versus 2.2% with placebo 5, 6. Patients should be counseled to abstain from sexual activity when lesions or prodromal symptoms are present and to use condoms consistently 1.

Special Populations

HIV-Infected Patients

HIV-infected patients require closer monitoring and may need longer treatment courses:

• For recurrent episodes: Consider standard regimens but monitor closely for treatment failure 3
• For suppressive therapy: Valacyclovir 500 mg twice daily has been effective in reducing recurrences and subclinical shedding 3, 1, 4
• In clinical trials, 65% of HIV-infected patients on valacyclovir 500 mg twice daily remained recurrence-free at 6 months versus 26% on placebo 5

Short-course therapy (1-3 days) should not be used in HIV-infected patients 3.

Orolabial HSV

Patients with orolabial lesions can be treated with oral valacyclovir, famciclovir, or acyclovir for 5-10 days 3.

Critical Clinical Considerations

What NOT to Use

Topical acyclovir is substantially less effective than oral therapy and should not be used 3, 1, 4. Systemic antiviral drugs partially control symptoms but do not eradicate latent virus or affect subsequent recurrences after discontinuation 3, 1, 4.

Monitoring Requirements

No laboratory monitoring is needed for patients on episodic or suppressive therapy unless substantial renal impairment exists 3, 1. For patients receiving high-dose IV acyclovir, monitor renal function at treatment initiation and once or twice weekly during treatment 3, 1.

Common side effects include nausea and headache 3, 1.

HSV-1 vs HSV-2 Prognostic Differences

Type-specific identification has important prognostic value: HSV-1 genital infections recur much less frequently than HSV-2 2. While the same treatment regimens apply to both types 1, patients with HSV-1 genital infections rarely require suppressive therapy due to infrequent recurrences 2.

Treatment Failure and Resistance

Suspect acyclovir resistance if lesions do not begin to resolve within 7-10 days after initiating therapy 3, 1. Obtain viral culture of the lesion and perform susceptibility testing to confirm drug resistance 3, 1.

For confirmed acyclovir-resistant HSV, IV foscarnet 40 mg/kg every 8 hours is the treatment of choice 3, 1.

Other reasons for treatment failure include incorrect diagnosis, co-infection with another STD, HIV infection, or poor medication adherence 3, 1.

Patient Counseling Essentials

Counseling is an integral part of management and should include 1, 4, 2, 7:

• Genital herpes is incurable but controllable with antiviral therapy 2
• Asymptomatic viral shedding can occur, allowing transmission even without visible lesions 2
• Condom use should be encouraged with all sexual partners 1, 2
• Childbearing-aged women must inform obstetric providers due to neonatal transmission risk 2
• Partners should be tested using type-specific serology before initiating sexual activity 3