Home remedies for fever blisters
Fever blisters are cold sores caused by herpes simplex virus; comfort care helps, but persistent or severe sores need assessment.
The short answer
Fever blisters are cold sores caused by herpes simplex virus, and home care can reduce irritation while the sore heals. Keep the area clean, avoid picking it, and protect it from friction; a clinician can prescribe an antiviral when treatment is appropriate.

What is the direct answer?
What does this question mean?
A fever blister is usually a small group of fluid-filled blisters on the lip or nearby skin, followed by crusting. It is different from a canker sore, which usually forms inside the mouth and is not typically a cluster of blisters on the lip margin.
What can you do next?
Use a cool, damp compress for short periods, drink cool fluids, and choose soft foods if chewing irritates the sore. Wash your hands after touching your mouth, avoid kissing or sharing cups and lip products, and ask a pharmacist or dentist about an antiviral cream or medicine, especially when the tingling phase has just begun.
When should you seek dental care?
Arrange an assessment if the sore is near the eye, lasts longer than expected, returns often, becomes unusually large or painful, or makes drinking difficult. Seek prompt medical care for spreading redness, marked swelling, fever with a very unwell feeling, or sores in someone with a weakened immune system.
What should you ask the dentist?
Ask whether the lesion looks like a cold sore or another mouth condition, whether an antiviral is suitable, and how to reduce spread to family members. Also ask what changes should prompt review if the sore does not heal.
Frequently asked questions
Can I pop a fever blister?
Do not pop it. Opening the blister can irritate the skin and transfer virus-containing fluid to nearby areas.
Is a fever blister the same as a mouth ulcer?
Usually not. A cold sore is commonly a clustered blister on the lip edge, while a mouth ulcer is an open sore inside the mouth.
