Request an online visit for Cold sores. A licensed provider reviews your case and prescribes treatment when appropriate.
Board-Certified · Internal Medicine · Medical Director
All 50 states + DC·Video visit
In-network: Aetna, BCBS, UnitedHealthcare +18 more plans
Cold sores (oral herpes) are caused by herpes simplex virus type 1, less often type 2. After primary infection — often in childhood — the virus stays latent in the trigeminal ganglion and reactivates as clusters of painful vesicles on or around the lips, frequently triggered by sun exposure, stress, illness, or hormonal change. Most outbreaks resolve in 7–10 days. Antiviral therapy (acyclovir, valacyclovir, famciclovir) started at the earliest prodrome — tingling or itching — shortens episodes; daily suppressive therapy is an option for frequent recurrences.