A randomized clinical trial on the treatment of oral herpes with topical zinc oxide/glycine

Altern Ther Health Med. 2001 May-Jun;7(3):49-56.


Context: A zinc preparation that provides a higher concentration of solubilized zinc in a minimally irritating formulation allowing controlled absorption would be of great clinical value for treating oral herpes.

Objective: To determine the effect of zinc oxide/glycine cream as a treatment for facial and circumoral herpes infection by measuring duration and intensity of signs and symptoms and assessing adverse effects.

Design: Double-blind, placebo-controlled, randomized clinical trial.

Setting: Subjects were enrolled from the general community through advertisements.

Patients: Forty-six subjects with facial or circumoral herpes infections.

Intervention: Application of a zinc oxide/glycine cream or a placebo cream every 2 hours until cold sore resolved or 21 days elapsed.

Main outcome measures: Duration of cold sore lesions, severity of signs and symptoms, and frequency of adverse effects.

Results: Subjects who began treatment with a zinc oxide/glycine cream within 24 hours of onset of signs and symptoms experienced a significantly shorter duration of cold sore lesions (mean, 5.0 days) than did subjects treated with a placebo cream (mean, 6.5 days). Subjects treated with the zinc oxide/glycine cream also experienced reduction in overall severity of signs and symptoms, particularly blistering, soreness, itching, and tingling. Side effects among subjects treated with zinc oxide/glycine cream were those expected from an ionic zinc salt solution. All were completely reversible and of short duration.

Conclusion: Zinc oxide/glycine cream is an effective treatment for facial and circumoral herpes infection with predictable adverse effects that are completely reversible.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Administration, Topical
  • Adolescent
  • Adult
  • Aged
  • Dermatologic Agents / administration & dosage
  • Dermatologic Agents / therapeutic use*
  • Double-Blind Method
  • Drug Administration Schedule
  • Female
  • Glycine / administration & dosage
  • Glycine / therapeutic use*
  • Herpes Labialis / drug therapy*
  • Humans
  • Male
  • Middle Aged
  • Treatment Outcome
  • Zinc Oxide / administration & dosage
  • Zinc Oxide / therapeutic use*


  • Dermatologic Agents
  • Zinc Oxide
  • Glycine