Praxis Medical Insights

Est. 2024 • Clinical Guidelines Distilled

Made possible by volunteer editors from the University of Calgary & University of Alberta

Last Updated: 8/27/2025

Management of Fever Blisters

Understanding Fever Blisters

  • Herpes labialis, commonly known as cold sores or fever blisters, is primarily caused by HSV-1 and affects 20-40% of the adult population, with recurrent episodes that can be frequent, painful, long-lasting, and socially embarrassing for infected patients, and the virus establishes latency in sensory ganglia and reactivates due to triggers like ultraviolet light exposure, fever, psychological stress, and menstruation 1

Available OTC Treatment Options

  • Topical anesthetics, zinc-based creams, and herbal-based products have limited evidence supporting their effectiveness and provide only modest clinical benefit compared to oral antiviral therapy, according to the Journal of Clinical Virology 2