I have a cold sore on my lip
A cold sore is a recurring blister caused by herpes simplex virus, usually on the lip border, and it often heals without dental treatment.
The short answer
Cold sores usually begin with tingling or burning, followed by grouped fluid-filled blisters that crust as they heal.
Why can a cold sore return after it has healed?
The virus remains dormant in nearby nerve tissue and can reactivate with triggers such as illness, sun exposure, stress, or local irritation.
How can you reduce irritation and spread from a cold sore?
Keep the area clean, avoid picking it, wash hands after touching it, and avoid kissing or sharing lip products while a blister or crust is present.
When should a cold sore be assessed by a dentist or doctor?
Seek care for an eye symptom, widespread lesions, severe dehydration, immune suppression, or a sore that does not follow its usual healing pattern.
What should you ask about treating and protecting others?
Ask whether an antiviral is appropriate, how to protect dental staff and family members, and whether the lesion could instead be an ulcer or bacterial infection.
Frequently asked questions
Can a cold sore occur inside the mouth?
Herpes lesions can affect oral tissues, but a single ulcer inside the cheek or lip is often a different condition and needs examination if unclear.
Can I have dental treatment with one?
Call the practice first because the lesion, procedure, and contact precautions affect the appointment plan.
Who wrote this page
This library is published by Dental Nation, a licensed dental group practising in the United Arab Emirates. Pages are written and overseen by the same clinical team that treats patients in our clinics, and are held to a fixed editorial standard for safety and accuracy.
This page is patient education, not medical advice, and cannot replace an examination. Anything urgent — facial swelling, trauma, uncontrolled bleeding or severe pain — needs a dentist or emergency care now.