What is the recommended treatment for a patient with Herpes Simplex Virus Type 1 (HSV-1) infection?

Treatment of Herpes Simplex Virus Type 1 (HSV-1) Infection

For HSV-1 infections, oral antiviral therapy with valacyclovir, acyclovir, or famciclovir is the recommended treatment, with specific regimens depending on whether the infection is initial, recurrent, or requires suppressive therapy. 1

Initial HSV-1 Infection

For first-episode HSV-1 infection, valacyclovir 1 g orally twice daily for 7-10 days is the first-line treatment. 1 Alternative options include:

• Acyclovir 400 mg orally three times daily for 7-10 days 1
• Famciclovir 250 mg orally three times daily for 7-10 days 2

Treatment may be extended beyond 10 days if healing is incomplete. 1

Recurrent HSV-1 Episodes (Episodic Therapy)

For recurrent HSV-1 outbreaks, treatment must be initiated during the prodrome or within 24 hours of lesion onset for maximum effectiveness. 1 Recommended regimens include:

• Valacyclovir 500 mg orally twice daily for 5 days 1
• Acyclovir 400 mg orally three times daily for 5 days 1
• Famciclovir 125 mg orally twice daily for 5 days 1

Herpes Labialis (Cold Sores) Specific Regimens

For orolabial HSV-1 (cold sores), single-day high-dose regimens are effective:

• Valacyclovir 2 g orally twice daily for 1 day (two doses 12 hours apart) 3, 4
• Famciclovir 1500 mg as a single dose 3

Treatment initiated during the prodrome significantly reduces healing time compared to waiting for visible lesions. 1

Suppressive Therapy

Daily suppressive therapy should be considered for patients experiencing ≥6 recurrences per year, which reduces recurrence frequency by ≥75%. 1 Recommended regimens:

• Valacyclovir 250 mg orally twice daily 1
• Valacyclovir 500 mg orally once daily (may be less effective in patients with ≥10 episodes per year) 1
• Acyclovir 400 mg orally twice daily 2
• Famciclovir 250 mg orally twice daily 2

Severe or Systemic HSV-1 Infection

For systemic HSV-1 infection (disseminated disease, encephalitis, or severe mucocutaneous disease), intravenous acyclovir 5-10 mg/kg every 8 hours is required. 3, 2

• Immunosuppressive medications should be temporarily reduced in transplant recipients or immunocompromised patients with systemic HSV disease. 3
• Continue IV therapy until clinical response is achieved, then switch to oral therapy to complete 14-21 days total treatment. 3

Special Populations

Kidney Transplant Recipients

• Superficial HSV-1/2 infections: Treat with oral antivirals (acyclovir, valacyclovir, or famciclovir) until all lesions resolve. 3
• Systemic HSV-1/2 infections: IV acyclovir plus reduction in immunosuppression, followed by oral therapy. 3
• Frequent recurrences: Use prophylactic antiviral therapy. 3

HIV-Infected Patients

• Acute episodes can be treated with the same regimens as immunocompetent patients. 3
• For frequent or severe recurrences, daily suppressive therapy with oral acyclovir or famciclovir is recommended. 3
• Acyclovir-resistant HSV (which occurs in immunocompromised patients): Treat with IV foscarnet or cidofovir. 3

Pregnant Women

• For frequent, severe recurrences of genital HSV during pregnancy, acyclovir prophylaxis may be indicated, with no pattern of adverse pregnancy outcomes reported. 3

Pediatric Patients

• Valacyclovir is approved for cold sores in children ≥12 years. 4
• All CMV disease in pediatric kidney transplant recipients should be treated with IV ganciclovir (not applicable to HSV-1 but relevant for transplant context). 3

Critical Treatment Principles

Topical acyclovir is substantially less effective than systemic treatment and should not be used as monotherapy. 1, 2

Treatment effectiveness decreases significantly when initiated beyond 72 hours of symptom onset for recurrences. 1, 4

Valacyclovir and famciclovir offer superior bioavailability and more convenient dosing compared to acyclovir, potentially improving adherence, though acyclovir remains effective and less expensive. 5, 6, 7

Patient Counseling

Patients must understand that HSV-1 is a chronic, incurable infection with potential for lifelong recurrence. 1

Patients should receive a prescription for antiviral medication to self-initiate at the first sign of recurrence (prodrome). 1

Asymptomatic viral shedding can occur with HSV-1, though less frequently than HSV-2, and transmission can occur during asymptomatic periods. 1, 6

Patients should avoid sexual contact when lesions or prodromal symptoms are present. 1, 4

Common Pitfalls to Avoid

• Do not delay treatment beyond 24 hours for recurrent episodes or 72 hours for initial episodes. 1, 4
• Do not use topical antivirals as sole therapy—they have poor efficacy. 1, 2
• Do not fail to consider suppressive therapy in patients with frequent recurrences (≥6 per year). 1
• Do not use genital herpes short-course regimens (3-5 days) for herpes zoster—this is inadequate for VZV infection. 3