1. If a blister is large or painful you can drain it with a straight pin that has been sterilized with rubbing alcohol. Once you've pierced it, gently press down on the blister so the liquid drains out of the puncture.
2. Once the blister is drained, wash the affected area gently with soap and water. Don't remove the skin flap on the blister, as the skin helps healing and prevents infection.
3. Apply a layer of antiseptic ointment and cover with a clean bandage. Change the bandage once a day or when it gets dirty.
A version of this article appeared in our August 2014 issue with the headline, “How to treat a blister,” p. 32.