How to Get the Swelling Down From a Fever Blister

Swelling is a prominent feature of all fever blisters. In the June 9, 2008 edition of “Archives of Internal Medicine,” Northeastern Ohio University dermatologist Dr. Christina Cernik explains that mild swelling precedes the appearance of a fever blister 1. The appearance of a fully developed fever blister is sometimes compared to a “dew drop on a rose petal,” Cernik says, because the blister--or dew drop--sits on a bed of red raised skin, or petals. Swelling of the surrounding skin persists even when the blister itself ruptures. Regardless of the stage of the infection, you can do a few things to get the swelling down from a fever blister.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.

See Your Doctor

Make an appointment with your doctor as soon as you suspect you are developing a fever blister. Let the receptionist know you need an appointment right away because, according to Cernik, antiviral medications are most effective when they are started immediately after symptoms appear. Be sure to have your personal calendar and a pen handy when you call, so you can make a note of the date and time.

Prepare a list of all of the names and doses of all of the medications that you currently take. Be sure to include any over-the-counter medications you use regularly, as well as dietary supplements such as vitamins or herbal preparations. Also note any cleansers, creams or cosmetics you normally use as part of your regular skin care regimen.

Arrive at the appointment at least 10 minutes early. Bring the list you prepared in Step 2, evidence of insurance coverage, a form of identification and a method of payment.

Talk to your doctor about your symptoms. Ask if antiviral drugs are right for you. Also ask if it's safe to continue your current skin care regimen during the outbreak.

Fill your prescription immediately, if you receive one. Ask your pharmacist how to use the medication if you have not used it in the past.

Ice the Affected Area

Fill the plastic bag with ice and cold water and seal it.

Cover the bag with a few layers of paper towels.

Apply the bag gently to the fever blister. Hold it upright to prevent leaking. Limit each session to 20 minutes or when you lose sensation in the surrounding skin.

Remove the bag. Allow the skin to reach room temperature.

Repeat, if desired. Always discard the paper towel when you are done.

Apply Astringent

Wash the skin surrounding the fever blister with mild cleanser and warm water. Wash the fever blister itself by gently irrigating with cleanser and water. Direct touching or rubbing can increase the irritation and swelling.

Pat dry gently with a paper towel. Discard the towel.

Apply a small amount of astringent solution to a clean cotton swab.

Apply the swab to the swollen skin, covering all affected surfaces. Discard the swab.

Repeat up to three times per day, or as directed by the astringent package instructions.


Antiviral drugs fight fever blister swelling by stopping the formation of new fever blisters and promoting the healing of existing fever blisters. Always complete the entire course of prescribed medication, even if your symptoms resolve sooner. recommends alternating warm and cold compresses to ease fever blister pain Cold compresses stop swelling, while warm compresses promote drainage. Try warm compresses at night, in conjuction with an upright position, when you do not care about skin’s appearance.

In the 2008 edition of “Fitzpatrick’s Dermatology in General Medicine,” University of North Carolina dermatologist Dr. Craig N. Burkhard explains that astringents such as aluminum acetate, witch hazel and other over-the-counter products cause tissue to contract and stop secretions. Since they can irritate healthy skin, apply them only to swollen skin.


Avoid squeezing, picking or playing with fever blisters. Not only does this increase swelling, it increases the potential for the fever blisters to develop scars and secondary bacterial infections.

Use disposable paper towels to clean your face and hands while you have fever blisters. Otherwise, people who inadvertently share your towels may pick up the infection, or you may spread it to other sites on your own body.

Talk to your doctor before you use cosmetics to conceal a fever blister. If you normally apply cosmetics with your fingertips, your cosmetics may contain bacteria that can superinfect the fever blister. When you apply cosmetics during an outbreak of fever blisters, always wash your hands before and after you apply, or use a disposable applicator, such as a cotton swab. Cosmetics that come into contact with the herpes simplex virus can spread it to unaffected skin, causing fever blisters to develop on new skin sites.