About 6 months ago my wife and I went to Costa Rica for 8 days. We snorkeld, went ocean fishing on a boat, We did the canopy tour on the cables (the leather gloves they gave us were pretty well used and of course sweated in by many different tourist and we river rafted. I now am getting rashes between both of my pointer and index fingers. They are little bumps and are clear and itch like hell! I also got a rash on my stomach shortly after getting back and my doctor gave me a shot in the hip of cortozone I think. It hurt like heck also. This rash on my fingers comes and goes any help appreciated. I think it was caused from the nasty leather gloves used on the canopy tour. So beware if you plan to do this. Bring some cotton gloves to wear under their gloves. Brett

Didn't your doctor recognize what it was? It sounds like athlete's foot and possibly ringworm. It does not have to be on the foot. There are many treatments for that at the drug store.

Also, you may want to try Grapefruit Seed Extract from the health food store, applied to the area. That should make ringworm disappear really fast.

Try another doctor's advice.

I'm so glad you re-opened this question! I do have an answer, at least for my own hands. It is caused directly by exposure to sunlight. It's taken me almost 30 years to rule out all other causes. That is why they appear in the summer, or when you're visiting Florida, etc. You're simply exposing your hands to more sunlight. You can even test it by covering up most of your hand when you go out in the sun. You will only get the blisters on the part that received sunlight.