Blister Basics

I have developed a blister.  Now what?


If you can figure out why the blister developed, it will be easier to understand what to do to prevent the blister from becoming worse.  Some possible causes:

• Ill-fitting shoe (too loose, too tight, loose heel pocket)
• Pressure Point(s)
• Toenails hitting front of shoe
• Callous/thick skin rubbing next to soft/supple skin

Where is your blister located?

• Heel
• Side of foot
• Next to a callous
• Between toes
• Under a toenail
• Tip of toe

 
Is the pressure ok with the blister intact or do you need to lance it?
Depending on the location of the blister and your tolerance to pain, consider whether to lance or not.  If you do lance the blister, are you able to keep the area clean to prevent infection? 

Techniques

For basic, easy to access blisters, a traditional donut works well.  Cut an oval or circle from a piece of moleskin or molefoam 1/4" or so larger than the blister circumference.  Then cut a hole out of the circle just larger than the blister.  Peel off the sticky backing and stick to clean skin surface.  (If you are having trouble getting anything to stick to the skin, use tincture of benzoin on the skin to help increase the stickiness.)  Cover with a protective layer of paper tape, making sure the tape is smooth and not creating further wrinkles.  If the blister has been opened, a layer of 2nd Skin between the blister & donut soothes and protects the skin.

You can modify this technique to use for various scenarios.  I will often use a smaller, second donut on top of the first (looks like a topo map from above) if I need to raise the area around the blister to alleviate pressure.  If a full donut won't fit, you can contour strips of moleskin instead.  This often works for the blister that develops on the side of the foot next to a callous. 

Ends of toes can be a challenge.  If there is enough room in the shoe without causing further pressure, try a small donut.  Very carefully tape a toe-width strip up & over the top.  Add tape wraps around the toe, smoothing out any wrinkles. 

Donuts can work well between the toes also.  Make sure you create enough space for the blister to reside within the donut hole.  Cover smoothly with tape.

Blisters developing underneath toenails can cause a lot of pressure to build up (even lifting the nail off its bed in extreme cases).  Lancing a blister such as this is more advanced and not for the faint of heart.  I'm not going to go into detail about that today. 
  
Bottom line:  Do your best to figure out and correct the cause of the blister.  Experiment to find what works for you.  If something doesn't work for you, change it on the trail, don't suffer if you don't have to!  

Suggestions for making your own "Blister Kit":

• scissors
• moleskin, molefoam
• Band-Aid blister blocks or similar gel-type pads
• Adhesive strips
• Paper (i.e., Micropore) tape
• Tincture of benzoin vials (available here or here)
• needle(s) and something to sterilize them with, such as a lighter
• Sterile gauze pads
• Water based gel pads (such as 2nd Skin) 

Here's an excellent article on blisters by WMI.