Herpes simplex virus type 1 symptoms (cold sores)

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Location of cold sores near mouth, with close-up of blisters

Herpes simplex virus type 1 (HSV-1) can cause groups of small blisters that usually appear on the lip and around or inside the mouth. The groups of blisters are commonly called cold sores. They may be itchy or painful.

Current as of: November 14, 2022

Author: Healthwise Staff
Medical Review:
Sarah Marshall MD - Family Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Kevin C. Kiley MD - Obstetrics and Gynecology

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