Cold sore Q&A
What causes recurring cold sore outbreaks?
Recurring cold sore outbreaks are caused by HSV-1 reactivating from the trigeminal ganglion, where the virus stays dormant after first infection. UV exposure is the single most controllable trigger: outbreaks spike in summer and after sun exposure. Stress, fever, and immune dips compound the risk. Standard lip balms make this worse: menthol and camphor compromise the lip's epidermal barrier. Labisan's 22% zinc oxide delivers mineral SPF 20 protection specifically designed to block the UV trigger at source.
Evidence
- UV radiation is the most documented environmental reactivation trigger for HSV-1 (herpes labialis); mineral zinc oxide at 22% blocks this directly at the lip surface.
- Menthol and camphor, present in most lip balms, are epidermal irritants that disrupt barrier integrity and extend cold sore recovery time.
- Graviola annonacin in Labisan's 22:1 immune capsules delivers an 8000mg daily equivalent to support the immune tone that keeps HSV-1 suppressed between outbreaks.
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