A lot has been said and written about blisters and backpacking — too much, really. Blisters are caused by friction, moisture, and heat. Under normal conditions, the conversation about blisters should be short:
Simple, right? If AT hikers do all these things, they can hike for six months without a single blister.
1. Choose Properly Fitting Boots/Shoes and Break Them in Before Your Trek
Boots/shoes should not be too snug or too loose — so when trying on shoes bring the two pairs of socks you will wear when hiking to the store. Ensure that there is ½ inch of space between your longest toe and the end of your shoe. Be sure that you have enough room to wiggle your toes inside the toe box, and your heel does not slip when you walk.
2. Wear Two Pairs of Socks
The oldest trick in the book. Wear a pair of 100% nylon men's dress socks under a pair of merino wool socks. Paired together, this sock combination makes friction take place between the two socks and not between your foot and the sock, preventing blisters. Also, never bring untested socks on a long hike. Try out your sock combination at home first to make sure it's comfortable.
3. Wear Gaiters
Gaiters prevent pebbles, leaves, twigs, et cetera from getting into your shoes and causing friction against your feet. Waterproof gaiters will help stop rain from getting inside of your boots.
4. Keep Feet Dry in the Snow & Rain
Northbounders starting in March or early April will likely experience snow at the beginning of their trip, and melting snow soon after. Southbounders will likely experience snow during the last month of their hike. The snow is rarely deep — you won’t be trudging knee-high through it — but there is enough to soak non-waterproof footwear and cause blisters. Whether you choose boots or shoes, they should have a waterproof liner like Gore-Tex or a durable water repellent (DWR) finish, or both.
With trail runners, snow easily gets over the top and then melts, soaking your socks and causing blisters. While waterproof gaiters can help slow how quickly that happens, they won’t prevent it. Boots paired with waterproof gaiters do a much better job at keeping snow out.
5. Wrap and Tape
People tend to get blisters in the same places. Some hikers always get blisters between their toes, others on their heels. If you know where you are prone to blisters, cover the area with Leukotape athletic tape, duct tape, or moleskin. We recommend you practice taping toes, heels, and the balls of the feet before leaving — it is important the tape be applied smoothly, without wrinkles, and not too tight. Wrapping one’s entire foot is unnecessary. Just tape the usual spots.
We prefer Leukotape over duct tape or moleskin. It molds to the contours of your foot better than duct tape and is cheaper than moleskin. Leukotape has an extremely strong adhesive that lasts for days and yet will not pull off skin when you remove it.
6. Treat Hot Spots Immediately
Before a blister appears, you will feel a hot spot. As soon as you feel a hot spot, stop and apply Leukotape to the area to prevent a blister from forming. You can use self-adhesive elastic bandage if the hot spot is between your toes.
7. Clean and Dry Your Feet at Night
After you get to camp it is important to take off your sweaty shoes and socks and let your feet dry out. If dirt has gotten into your boots, wash your feet with some of your drinking water. Only after your feet are completely dry should you put on your bedtime socks.
You followed all the preventative measures and yet still got a blister. Here's what to do:
Small blister with little fluid - treat like a hot spot
Larger blister with fluid
Large, broken blister
An often recommended treatment for blisters from runners, hikers, and military vets is compound tincture of benzoin. Available at any pharmacy, it doesn’t require a prescription but might be kept behind the counter. Tincture of benzoin comes in two forms, compound which is a treatment for damaged skin, and non-compound which is an inhalant.
Benzoin is the sticky sap of Styrax trees and its stickiness helps tape or bandages adhere longer to skin, though this is not necessary if you use Leukotape. Some guides say that tincture of benzoin accelerates blister hardening and even recommend injecting it into a blister. However this causes intense burning pain when it touches raw skin. It has a reputation for toughening skin where it is applied and many long distance walkers/runners/hikers apply it to sensitive areas every day for a few weeks to toughen those areas.
The trouble: Tincture of benzoin was invented in the 19th century and its many supposed benefits have never been evaluated by the FDA. Like vitamin supplements, it is legal to sell only because manufacturers follow certain regulations. We consider it a folk remedy with no merit — a hiker's urban legend — and do not recommend it.