This article is based on what I presented in the Beginner Backpack Workshop held by Appalachian Mountain Club, Delaware Valley Chapter, April 22, 2006.

Cause of Blisters

The cause of blisters is friction. With enough rubbing, the tough epidermis which has been resisting abrasion separates and fluid fills in the space. A blister therefore forms.

A general guideline to prevent blisters from happening is to keep our feet cool and dry, because both heat and moisture increase friction. Heat makes the feet swollen and moisture softens the skin.

Prevention

The best way to deal with blisters is to prevent them, and prevention can take place before heading out for a trip:

1. Find a pair of boots that fits your feet snugly.

2. Condition your feet: the best discipline is probably to walk in your bare feet as much as possible, or at least use your feet as much as possible.

3. Cover the blister-prone areas with athletic tape, moleskin, or other material.

4. Select a sock system that suits you.

During a trip, the following are what you can do:

1. Let your feet breathe more whenever you have a chance. For example, when taking a snack break, lunch break or whatever break that is longer than several minutes long, take your feet out of your boots to cool them down. Never underestimate these few minutes of air cooling process, because it in fact reduces the degree of swelling significantly.

2. Prepare two pairs of socks and rotate them. If your feet tend to sweat a lot or you are hiking in on an extremely hot and humid day, it’s nice to prepare an extra pair of dry socks to replace those damp ones on your feet. Once you rotate them, you can hang those wet ones on your pack to air dry them. Just make sure none of your teammates gets too close to them!

3. Elevate your feet when you have a longer break. Foot elevation is to help better blood circulation, which will take heat away from the feet more efficiently and reduce the swelling.

4. Remove dust and small rocks out of socks and boots. Keeping your boots and socks as clean as possible is another way to reduce unnecessary rubbing. Therefore when you feel dust and rocks touch your delicate feet, spot them and remove them.

5. Give your feet a break by hiking in sports sandals occasionally. Many people are skeptical about hiking in sports sandals, but if your feet are good and the trails are well-maintained, I don’t see why you can’t hike in sports sandals, especially modern sports sandals have good cushion and stability. I, myself, have backpacked in sports sandals numerous times and I enjoyed the air flow through my feet. Hiking in sports sandals gives your boots and socks a rest especially in extremely humid days. I’ve tried Teva, Chaco, and Keen Footwear and they are all great. Keen Footwear sandals cover the toe areas, which might make hikers more comfortable if they are concerned about protection. However, since Keens cover more area and make more contact with the feet, my feet usually get more sweaty in them than in Teva or Chaco and I got blisters at the sides at times. (To avoid it, I can wear a pair of thin liners or tape those areas before putting my feet in the sandals.) Most people bring sports sandals as camp shoes, and they are handy for river crossing, so why not give them a shot next time?

When There Are Hot Spots/Redness/Small Blisters

When you feel there are hot spots on your feet or when you inspect your feet during a break and spot a faint redness or a small blister, DO SOMETHING! Don’t naively think they will go away and it’s certainly not the time for you to play a hero.

You should cover the area to prevent further rubbing, and the material you can use include athletic tape, surgical tape, band-aid, moleskin, Spenco Second Skin, and so on. Go to a local drugstore, you will find plenty on the counter. Some hikers prefer duct tape, but I’ve never done that before because duct tape seems to be too sticky to me.

When There Are Big/Painful Blisters

I hope you don’t have to come this far, but if you really get a big blister and it causes pain or unease and it prevents you from walking straight, drain it and cover the area. How? Here are the steps:

1. Clean the area.
2. Sterilize a needle and use it to make holes around the base of the blister.
3. Drain the blister by gently compressing the blister.
4. Apply antibiotic ointment to the area, and cover it with gauze.
5. Cut a donut-shaped piece of moleskin, molefoam, etc, and center the paddling over the area.
6. Tape the area.
7. Clean daily and monitor for signs of infection.

Reference

Tod Schimelpfenig and Linda Lindsey. NOLS Wilderness First Aid. Second edition.
Frank Hubbell. SOLO’s Field Guide to Wilderness First Aid.