Cold Sores

Also known as: fever blisters, herpes simplex virus 1, HSV-1

What are cold sores?

Cold sores are common small painful blisters that usually appear on or around the lips, mouth, nose, or face and are frequently called "fever blisters." They typically last up to 2 weeks and tend to recur in children frequently after experiencing stress.

What causes cold sores?

Cold sores are caused by a viral infection from herpes simplex virus 1 (HSV-1) which is spread by kissing, close contact, or sharing eating utensils with someone who is infected.

What are the signs/symptoms of cold sores?

Before the red blisters appear, the mouth/lips may feel itchy or tingly. After the blisters appear, they can ooze and crust over. Fever, sore throat, headache, eating difficulties and swollen neck glands may also occur.

What are cold sore care options?

Cold sores usually clear up on their own within a week or two. For help in speeding the process along, and relieve discomfort and pain, antiviral creams and pills are recommended.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: August 30, 2021 04:53 PM

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