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How To Prevent And (If You Must) Treat Foot Blisters

by Bill Greer

In this article I’ll discuss the cause, prevention, and treatment of friction blisters.  Much good research has been done by your US Army on this subject.  As you can imagine blisters are a continuing problem for the Army, particularly in “boot camp” where new recruits who maybe haven’t done much walking are suddenly doing a lot of it.  Make no mistake about it; a blister can be a serious injury.  Bad blisters have required hikers to be evacuated.  Like any serious injury it’s much better to prevent a blister than treat it properly.  I’ll talk about what causes blisters and how to prevent them first.

Your skin is composed of several layers.  When subjected to back-and-forth friction the bond between these layers eventually breaks down and they separate.  Fluid leaks into the injured area and you have the painful, fluid filled bump we call a blister.
This damaging friction is cause by your feet moving around in your boots or shoes as you walk.  If you can prevent this movement you can prevent blisters.  It’s really that simple.  No movement, no blisters.  This movement can be caused by boots that don’t fit right or are not tight enough.

Your boots absolutely, positively, must fit you.  The better they fit the less you have to tighten them to prevent movement.  There are few ways to fix a poor fit.  They have to fit right when you buy them.  Don’t count on them “breaking in.”  Modern boots don’t need a lot of breaking in (more on that later.)  Don’t buy Brand X because your buddy has them and loves them.  Your feet might be shaped differently.  They should feel comfortable but not allow movement.  Go when the store is not busy so the boot expert has time to work with you until you find the pair that your feet will be happy with.  Try many different boots.  Different stores carry different brands and models and they all fit differently so look around if your feet don’t say “ahhh” to the first pair you try.

Men’s and women’s boots are built pretty much the same but women’s boots tend to be a bit narrower at the heel for the same width up front.  If you’re a guy with a narrow heel or a woman with a wide heel try the other boots.  It won’t mess with your hormones a bit but may make your feet happier.  If you are having problems with heel blisters this can sometimes cure them.

On the trail tighten your boots if you see a long downhill coming.  On a downhill trail your feet will want to slide forward when you put weight on them, and then slide back when you pick them up.  This back-and-forth motion is perfect for generating blisters.  On a level trail boots that are too loose can let your heels move up and down resulting in a heel blister.  Snug them up, then take them off and let your feet breath when it’s break time.

DO NOT wear cotton socks!  Research by the Army and by runners has shown that synthetic socks are much less likely to cause blisters.  When you get a blister it will be larger with cotton socks than with synthetic socks.  Wool/synthetic blends work well too.  Cotton socks take forever to dry if they get wet. 

Most people like to wear a thin synthetic liner under a heavier outer sock.  Then at least some of any friction that takes place will be between socks rather than between sock and skin.  The advantage of this is that socks don’t get blisters. 

Change socks if they get too wet or stinky.  You can rinse them out in a stream (without soap) and hang them to dry on your pack.

The Army experimented with using antiperspirants on feet on the theory that this would keep feet drier and less prone to blisters.  It did reduce the frequency of blisters but the somewhat toxic chemicals confined inside boots cause a variety of more serious skin problems.  Leave the chemicals at home.  Nobody will mind the stink and the sweat will dry quickly if socks are hung on the outside of your pack.

A blister may just be nature’s way of showing where you need a callus.  Introduce your feet to walking gradually.  As you build up the miles you will toughen your feet and get them ready for long hikes without blisters.  Your boots and your feet will both break in together.  The Army has found this to be helpful for new recruits.

If you fail to prevent a blister the next best thing is catching it as soon as possible.  Pay attention to your feet as you walk.  At the first sign of a problem attend to it.  A few minutes spent adjusting boots or socks, or putting on a piece of tape, is much better than dealing with a serious injury later.

The first sign of an impending blister is a “hot spot.”  This red, irritated area shows where you are experiencing friction and where you will soon have a blister if you don’t do something about it.  It’s much better to catch the injury at this point than waiting until a blister forms.  It will heal much faster and not be nearly as painful. 

Treat a hot spot by covering the area with a thin, slick tape such as 3M “Durapore”.  This surgical tape is waterproof, designed for use on skin, and has a satin surface that socks will slide over with a minimum of friction.  It’s also stretchy so it conforms to the shape of your foot better than some other tapes.  Moleskin is thicker so it increases pressure on a spot that’s already tender and has a high friction surface that’s not what you want.  Most good drug stores and big grocery stores carry it.  Sometimes the label says something else and you have to look at the inside of the spool to see the Durapore name.  I’m sure there are other tapes that would work well too.  After you’ve applied tape be sure your boots aren’t too loose.

If you let things go long enough to get a blister (shame on you!) begin by covering the injury with a piece of “Second Skin”.  This is a tough jell that is mostly water.  It was first developed for treating burns but works really well for blisters too.  Drug stores sell burn kits that I like because they have smaller pieces of the stuff.  After you cut a piece to cover the blister peel the plastic film off of one side and put that side on the blister.  Cover the second skin with generous amounts of water proof tape.  If you’re desperate and Durapore won’t keep the Second Skin in place some people have had good results with duct tape.  This should be a last resort because it can be very hard on your skin.

Try to avoid draining a blister if you can.  Sometime they get so huge that you have no choice, but it’s better avoided if you can.  Intact skin will protect your injury from infection.  If you must drain one sterilize a needle with a match and puncture the blister.  Then gently press out the fluid.

Whether you’ve treated a hot spot or blister remove the tape at night and let your feet dry and get fresh air.  A soak in a cold stream can feel wonderful.

I hope all this helps you avoid blisters.  May your feet always be happy!

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