Up to 2 to 3 weeks from tingle to healed skin - and the blister days are the most contagious.
The stages run tingle, blister, weep, crust, heal. MedlinePlus notes oral herpes spreads most easily from an active sore, so no kissing or shared lip products during an outbreak. Antivirals work best started at the first tingle, before the blister forms - frequent sufferers can keep a supply on hand.
What to do
Common questions
How long does a cold sore last?
Figure on up to 2 to 3 weeks from first warning to fully healed skin, though most resolve closer to the shorter end. The stages run predictably: a day or two of tingling, itching, or burning on the lip line, then blisters, then weeping and crusting, then healing. MedlinePlus notes oral herpes symptoms can last up to 3 weeks and spread most easily from an active sore - so the blister and weeping days are peak contagious: no kissing, no sharing lip products, towels, or razors, and wash hands before touching contact lenses or a baby. The intervention that changes the course is timing: prescription antivirals work best when started at the first tingle, before the blister forms, and people with frequent outbreaks can keep a supply on hand for exactly that moment. Docosanol cream from the pharmacy is the milder over-the-counter option. Sores that spread to the eye, last beyond two weeks, or hit someone immunocompromised need a doctor promptly. Pymander, a free AI doctor available 24/7 by text, can help you plan around an outbreak.