How to Treat a Blister Safely

Foot blister
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Most walkers and runners get a foot blister from friction from time to time. Toes, heels, and the sole of your foot are all prime areas for friction blisters as you foot rubs against your sock and shoe with each step. Here are the steps to treat them.

Protect the Blister and Allow It to Heal

This is the safest course of action for all blisters, but especially those that are under the size of a pea.

Blisters of that size will usually heal within a couple of days although you'll want to protect the area from further rubbing and friction for at least a week.

  • Clean the area with mild soap and water and allow it to dry.
  • Cover the blister with a bandage.
  • You may want to make a donut area around the blister to protect it further, cutting strips of moleskin to encircle it.
  • Check your footwear and switch to shoes or sandals that won't rub against the blister area.
  • Learn your lesson, what did you do or didn't you do that led to getting the blister

Deciding to Drain a Blister

  • Never drain a blister of any size if you have a condition that leaves you more prone to developing an infection, such as diabetes, cancer, heart disease, or HIV.
  • Never drain a blister that was produced by a burn or an infection rather than from friction: Is your blister from something other than friction? Then draining it could just make an infection worse or risk giving yourself a new infection.
  • Draining a blister always includes a risk of infection. But if the blister has already torn or is protruding, tense, bulging and likely to burst, you may consider draining it now so you can cover it and protect it while it heals.

What You Will Need to Drain a Blister

  • Sterile needle
  • Antibiotic ointment
  • Rubbing alcohol
  • Bandage

Here's How to Drain a Foot Blister Caused by Friction

  1. Swab the blister area with rubbing alcohol and it let air dry. Allowing it to dry kills more bacteria on the skin and prevents the alcohol from causing stinging when you drain the blister.
  2. Look for a packaged sterile needle in your first aid kit. If you don't have one, locate any clean needle or even a clean safety pin. Sterilize the needle for 10 seconds in a flame. Don't burn yourself in the flame or you will now have blisters on your hand as well as your foot.
  3. Puncture the edge of the blister near the skin. You want to create the smallest possible hole, you don't want a large hole or a cut. Every opening in the skin increases the risk of infection.
  4. Apply gentle pressure to squeeze out the blister fluid.
  5. Do not remove the top of the blister or rub it off.
  6. Apply antibiotic ointment, but avoid alcohol or iodine.
  7. Cover the drained blister with sterile gauze or a bandage.
  8. Discard the needle into sturdy plastic or metal container. Don't keep it to reuse.
  9. Keep the bandaged area clean and protected.
  10. Switch to shoes or sandals that won't rub against the area of the blister while it is healing.
  11. Change the gauze or bandage daily.
  12. If pus or redness develops, seek medical attention. Those are signs of an infection, and the sooner you get it treated the better. The foot and toes can be hard to treat well when infected and you risk gangrene.

    While Your Blister Is Healing

    Your gait will probably be gimpy as you naturally protect the blistered area, which will probably hurt. You can expect to end up with sore muscles due to this unnatural walking pattern.

    Check for signs of infection and get medical help as soon as possible if they develop.

    It often takes about a week for a blister to heal well enough to remove the bandage. You can expect the area to be prone to getting a blister again for at least two weeks, so you need to take precautions.