What is the first line treatment for herpes labialis?

First-Line Treatment for Herpes Labialis

The first-line treatment for herpes labialis (cold sores) is valacyclovir 2g twice daily for 1 day, which should be initiated as early as possible during the prodromal phase for maximum efficacy. 1

Recommended Oral Antiviral Options

• Valacyclovir 2g twice daily for 1 day is recommended by the American Academy of Dermatology as the most effective short-course regimen for adults with herpes labialis 1
• Famciclovir 1500mg as a single dose is an effective alternative, reducing median time to healing by 1.8 days compared to placebo (4.4 days vs 6.2 days) 2
• Acyclovir 400mg five times daily for 5 days is another option but requires more frequent dosing, making it less convenient 1

Treatment Timing and Efficacy

• Treatment should be initiated during the prodromal phase or within 24 hours of symptom onset for maximum effectiveness 1
• Early treatment is crucial as efficacy decreases significantly when treatment is delayed beyond the prodromal phase 1
• Single-day high-dose regimens (valacyclovir, famciclovir) offer better compliance than multi-day treatments 1

Management of Lesions

• For intact blisters, the British Association of Dermatologists recommends gently piercing them at the base with a sterile needle to drain fluid while keeping the roof intact as a biological dressing 1
• Applying petroleum jelly can support barrier function and encourage healing 1

Suppressive Therapy for Frequent Recurrences

• For patients experiencing six or more recurrences per year, suppressive therapy is indicated 3
• First-line suppressive therapy options include:
  • Valacyclovir 500mg once daily (can increase to 1000mg once daily for very frequent recurrences) 3
  • Famciclovir 250mg twice daily 3
  • Acyclovir 400mg twice daily 3
• Daily suppressive therapy reduces the frequency of herpes recurrences by ≥75% among patients with frequent recurrences 3

Important Clinical Considerations

• Topical antivirals provide only modest clinical benefit and are less effective than oral therapy 3
• Relying solely on topical treatments when oral therapy is more effective is a common pitfall to avoid 3
• Despite increasing use of HSV-specific antiviral agents, the incidence of resistant HSV-1 strains remains low (<0.5% in immunocompetent hosts) 3
• For immunocompromised patients, higher doses or longer treatment durations may be required 3

Duration of Suppressive Therapy

• Safety and efficacy have been documented for acyclovir for up to 6 years 3
• Valacyclovir and famciclovir have documented safety for 1 year of continuous use 3
• After 1 year of continuous suppressive therapy, consider discontinuation to assess the patient's rate of recurrent episodes 3