What is the treatment for oral herpes simplex infection?

Treatment of Oral Herpes Simplex Infection

For oral herpes simplex infection, the recommended first-line treatment is oral antiviral therapy with acyclovir, valacyclovir, or famciclovir, which should be initiated as early as possible to reduce viral replication and prevent complications. 1, 2

First-Line Treatment Options

• For mild to moderate oral HSV infections in immunocompetent patients:

  • Acyclovir 400 mg orally three times daily for 5-7 days 1, 3
  • Acyclovir 200 mg orally five times daily for 5-7 days 1
  • Valacyclovir 500 mg orally twice daily for 5-7 days 1, 3
  • Famciclovir 250 mg orally twice daily for 5-7 days 1, 4

• Topical options (less effective than oral therapy):

  • Ganciclovir 0.15% gel applied three to five times daily 1
  • Trifluridine 1% solution applied five to eight times daily (not recommended for more than 2 weeks due to epithelial toxicity) 1

Severe Infection Treatment

• For severe oral HSV infections requiring hospitalization:
  • Intravenous acyclovir 5-10 mg/kg every 8 hours until clinical resolution 1, 2
  • Once lesions begin to regress, transition to oral therapy to complete treatment 2

Treatment in Immunocompromised Patients

• Initial treatment with IV acyclovir is recommended for immunocompromised patients 2
• Treatment should be continued until complete healing of lesions 2
• Short-course therapy should not be used in patients with HIV infection 2
• Higher doses or longer treatment duration may be necessary 5

Recurrent Episodes Management

• For frequent recurrences (≥6 episodes per year), suppressive therapy may be considered:

  • Acyclovir 400 mg orally twice daily 1, 3
  • Valacyclovir 500 mg daily or 1000 mg daily 1, 3
  • Famciclovir 250 mg twice daily 1, 6

• For episodic treatment of recurrences (start at first sign of prodrome):

  • Acyclovir 400 mg orally three times daily for 5 days 1
  • Valacyclovir 500 mg orally twice daily for 5 days 1
  • Famciclovir 125 mg orally twice daily for 5 days 1
  • Single-dose famciclovir may be effective for herpes labialis 7

Management of Treatment Failure

• If lesions do not begin to resolve within 7-10 days of therapy:
  • Suspect drug resistance 2
  • Obtain viral culture and perform susceptibility testing 2
  • For confirmed acyclovir-resistant HSV, IV foscarnet is the treatment of choice 2, 8

Monitoring During Treatment

• For patients on IV acyclovir, monitor renal function at initiation and once or twice weekly 2
• Dose adjustment is necessary for patients with renal impairment 2
• Follow-up within 1 week of treatment for HSV conjunctivitis 1

Important Caveats

• Topical antiviral therapy alone is substantially less effective than systemic therapy and should not be used as monotherapy for severe oral HSV lesions 2, 9
• Delayed treatment reduces efficacy; therapy should be initiated as soon as possible 2
• Immunocompromised patients may develop resistance more frequently 2, 8
• Topical corticosteroids potentiate HSV epithelial infections and should be avoided 1
• Patients with HIV may experience atypical and recalcitrant lesions 2

Special Considerations

• Neonates with HSV require prompt consultation with a pediatrician or primary care physician, as systemic HSV infection is life-threatening 1
• Patients with a history of HSV keratitis should receive specialist review and advice 1
• For patients with recurrent attacks, prophylaxis may be considered with acyclovir 400 mg twice daily, valacyclovir 500 mg daily, or famciclovir 250 mg twice daily 1