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Research · Systematic review

Interventions for prevention of herpes simplex labialis (cold sores on the lips)

What it found

Found no evidence of efficacy for lysine in preventing recurrent cold sores, and rated the overall evidence as very low quality.

Design
Systematic review
Year
2015
Sample size
2,640
Population
immunocompetent people with recurrent cold sores (32 RCTs)
Intervention
oral lysine and other preventive interventions vs placebo
Outcome
prevention of cold-sore recurrence
Journal
Cochrane Database of Systematic Reviews

Citation last checked 2026-06-21.