Fever blisters are also known as cold sores. They are caused by the herpes simplex virus. This virus remains in your body throughout your life and causes fever blisters to erupt several times per year. If you have a fever blister, you should work on getting rid of it because fever blisters are contagious. Be careful not to touch the fever blisters, and make sure to wash your hands regularly so that you do not spread this virus.
Clean the area before using the peroxide on your fever blister. Wet a washcloth with warm water and wipe it all over your face. Apply some facial soap by rubbing the soap on your face in tiny circles with the washcloth. Rinse the washcloth out and re-wet. Now rinse your face off with the washcloth and pat dry with a hand towel. Place both the washcloth and the hand towel in the washing machine so that you do not spread the herpes simplex virus to someone else in your home.
Pour some peroxide in a bowl and set a few cotton balls in it to soak. After you have cleaned your face, take one of those cotton balls and use it on your fever blister. Just wipe it back and forth over the fever blister a few times. The peroxide will dry the fever blister up so that it goes away. Fever blisters thrive in moist environments. By using the peroxide, you'll dry up the area and take away the moisture that the fever blister needs to survive. Apply the peroxide cotton balls three to four times per day until your fever blisters are gone. Do not use your hands to apply the peroxide to your fever blister, as this can spread the virus.
Another way to administer peroxide to a fever blister is to make a paste out of peroxide and aspirin. Crush up two aspirins and place the powder in a tiny bowl with 1 tsp. of hydrogen peroxide. Mix it together until you get a paste. Use a cotton swab to apply the paste to your cold sore. Leave it on for two to three minutes. Any longer can actually cause a burn to your skin. Do this once each day. Again, do not use your hands to apply this paste to your fever blister.