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Side Effect: Cold sores

What are cold sores?

Cold sores are tiny lesions that result from a common viral infection known as herpes simplex, otherwise known as HSV. The medical term for cold sores on the lips of the mouth is herpes labialis. Importantly, viral infections may appear on the inside of the mouth and may be mistaken for mucositis. In these instances, it is sometimes helpful to have a health care provider swab the area and send it for viral culture to see if anti-viral medication is needed.

What do cold sores look like?

Cold sores are eruptions of the skin that appear as tiny red blisters, and are often painful. They can appear on the lips, and may overlap the skin next to your lip.

Cold sores


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Prevention of cold sores:

For people who get frequent cold sores, either acyclovir or valacyclovir can be taken to prevent cold sores from appearing during treatment

Treatment of cold sores:

The sooner valacyclovir (Valtrex®) or Acyclovir therapy is started, the higher the chance that it will work to make the cold sore go away faster. Therefore, if a cold sore appears it should be treated as soon as possible.

Who gets cold sores?

When the immune system is not functioning at full capacity, cold sores may appear. Common conditions that may weaken your immune system, which may increase your risk of a cold sore include, but are not limited to:

How long do cold sores last?

Cold sores usually last for a few days before they begin to heal, and often take more than a week before they disappear completely

How do you prevent cold sores?

For patients with recurrent cold sores or for those who will be receiving treatment that increases the risk of recurrent cold sores, preventative antiviral therapy, known as prophylaxis, may be offered:

How do you treat cold sores?

Early treatment with an antiviral medication, such as acyclovir or valacyclovir, will help the cold sore heal faster, often by several days.

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Created: February 10, 2022 Updated: February 17, 2022