What is the recommended treatment for herpes simplex as a sexually transmitted infection (STI)?

Treatment of Herpes Simplex as an STI

For the treatment of genital herpes simplex virus (HSV) infection, oral antiviral therapy with acyclovir 200 mg orally 5 times a day for 7-10 days is recommended for first clinical episodes, while recurrent episodes can be treated with shorter courses of therapy. 1, 2

First Clinical Episode of Genital Herpes

Recommended Regimens:

• First-line therapy:
  • Acyclovir 200 mg orally 5 times a day for 7-10 days 1, 2

Alternative Regimens:

• Valacyclovir 1 gram orally twice daily for 7-10 days 3
• Famciclovir 250 mg orally three times daily for 7-10 days 4

Treatment should be initiated as soon as possible after symptoms appear, ideally within 72 hours of onset, as efficacy diminishes with delayed treatment 3.

Recurrent Episodes of Genital Herpes

Recommended Regimens:

• Acyclovir 800 mg orally three times daily for 2 days 5
• Acyclovir 800 mg orally twice daily for 5 days 2
• Acyclovir 400 mg orally three times daily for 5 days 2

Alternative Regimens:

• Valacyclovir 500 mg orally twice daily for 3 days 3
• Valacyclovir 1 gram orally once daily for 5 days 3

Treatment should begin within 24 hours of symptom onset or during the prodromal phase for maximum effectiveness 3.

Suppressive Therapy for Frequent Recurrences

For patients with ≥6 recurrences per year, suppressive therapy should be considered:

• Acyclovir 400 mg orally twice daily 2
• Valacyclovir 500 mg orally once daily (for patients with ≤9 recurrences per year) 3
• Valacyclovir 1 gram orally once daily (for patients with >9 recurrences per year) 3

Daily suppressive therapy reduces recurrence frequency by at least 75% among patients with frequent recurrences 2.

Special Considerations

HIV Co-infection

• HIV-infected patients may require longer courses of therapy and closer monitoring 1
• Consider using the 7-day erythromycin regimen for HIV-infected patients 1
• For suppressive therapy in HIV-infected patients with CD4+ count ≥100 cells/mm³, standard suppressive regimens are appropriate 3

Pregnancy

• Acyclovir can be safely used during pregnancy 2
• Cesarean delivery should be considered for women with active genital lesions or prodromal symptoms at the time of delivery

Acyclovir-Resistant HSV

For immunocompromised patients with suspected resistance:

1. Confirm resistance with viral culture and susceptibility testing if available
2. Consider foscarnet 40 mg/kg IV every 8 hours as alternative therapy 6
3. Topical trifluridine may be used for accessible lesions 6

Prevention and Counseling

• Consistent condom use reduces HSV-2 transmission 2
• Daily suppressive therapy with valacyclovir reduces risk of transmission to uninfected partners 3
• Patients should abstain from sexual activity when lesions or prodromal symptoms are present
• All patients diagnosed with HSV should be tested for other STIs including HIV 1

Follow-up

• Patients should be re-examined 3-7 days after initiation of therapy to assess treatment response 1
• If no improvement is seen, consider:
  1. Incorrect diagnosis
  2. Co-infection with another STI
  3. HIV infection
  4. Poor medication adherence
  5. Antiviral resistance 1

The time required for complete healing is related to the size of the ulcer; large ulcers may require more than 2 weeks to heal completely 1.