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Cold Sores

Also indexed as:Fever Blisters, Herpes Simplex 1
As soon as a cold sore appears, you’re ready for it to disappear. According to research or other evidence, the following self-care steps may be helpful.
Cold Sores: Main Image

About This Condition

Cold sores are painful fluid-filled blisters that form on the borders of the lips caused by a herpes virus, most often the herpes simplex 1 virus.

Cold sores should not be confused with canker sores, which are small ulcerations in the mouth. The blisters, which are contagious, later break, ooze, and crust over before healing. Recurrences are common and can be triggered by stress, sun exposure, illness, and menstruation. Genital herpes infection (usually caused by herpes simplex 2) is a related condition and potentially may be treated in much the same way as herpes simplex 1.

Symptoms

Cold sores may appear with colds, fevers, exposure to excessive sunlight, or menstrual periods, as well as during periods of stress or illness. The sores usually disappear within two weeks. Initially, there may be tingling or prickling at the site of the cold sores even before they are visible (called the prodrome); afterward, the blisters often weep a clear fluid and form a scab. If the infection is transmitted to the eyes, it may lead to blindness.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.