While a a meter of prevention is worth a kilometer of cure, even the most careful hikers still get blisters.
Never forget that blisters are a medical condition that require first aid. They can get infected, and infection can put you in the hospital and (a Pacific Crest Trail through-hiker was nearly killed by septic shock resulting from infected blisters in June 2007 — an extreme case but it shows they are not to be trifled with).
The best thing to do about a blister is to stop making it worse and let the body’s healing powers take over. Few humans have the time or inclination to do this because blisters always happen in the middle of a hike with several miles of foot punishment between them and the trailhead.
Blisters requiring treatment come in two shapes: either a layer of skin has been rubbed away completely by friction (usually on the heels or between the toes), or a little fluid-filled pouch between layers of skin has formed, causing pressure pain (usually on the more calloused areas of the feet).
The skin-rubbed-away blister
This has the most obvious treatment: clean it thoroughly with alcohol wipes and antibiotic ointment, put some gauze over the exposed area and tape the whole thing closed to prevent further friction. The exposed flesh will harden a bit when exposed to air, so let it breathe awhile before you apply the dressing and tape over the wound. Be extra careful not to tape over any loose skin, because it’ll just peel back off when you remove the tape.
The fluid-filled blister
This guy is much trickier: you have to judge whether to drain the fluid. What happened to me once: 10 miles of punishing terrain stood between me and a trailhead on an overnighter, and a fluid-filled blister was giving me fits. I decided the risk of making it worse outweighed the risk of puncturing the blister and draining the fluid.
On most day hikes of no more than a few hours, you’re probably better off taking it easy and letting the blister heal on its own, but if you’re going to be on your feet for a long time (all day or on a backpacking trip,) draining the blister is going to be pretty much mandatory.
If you do this, you must sterilize the tip of your puncture tool (preferably a needle to keep the hole as small as possible, but a knife can work). Don’t do it with a match: it won’t burn long enough to sterilize and it might introduce bits of soot if the metal oxidizes. Standard advice: Clean your hands and the wound area; using a lighter, burn the tip till it turns red, then let it cool. Make a tiny puncture at the edge of the blister and let the fluid drain.
Once you’ve done all that, clean the wound with your alcohol wipes and antiseptic ointment and let the remaining skin protect the wound. Cover with gauze and tape it closed, taking care not to tape any loose skin.
A milder fluid-filled blister might best be left alone or taped over to reduce friction. Walk more slowly, take more rest stops and air out your foot to cool it down when you rest.
Note that all this implies having a first aid kit. If you hike without one, you have to be doubly zealous about prevention.
These tips summarize several suggestions I’ve found at sites around the Web:
- This post at a blog called Montana Jones has lots of in-depth advice, and says the ever popular “moleskin” isn’t all that great.
- Dr. Stephen Pribut notes that diabetics should never treat their own blisters.
- Pacific Crest Trail Association has a great page of foot-health tips.
- The Happy Feet blog has tons of interesting info on pampering your tootsies. This page on lancing a blister is excellent.