Since I live in a moderate climate, I don't tend to have problems but recently, I've noticed my hands are sweating so much it's affecting my playing. Could be my age. I've tried liquid talc, which works to a degree but causes fret squeaks which isn't ideal if I'm recording, and any thing else I've tried leaves a sticky residue. Any ideas?
Maybe part of it is your diet. When I drank lots of coffee, my hands sweated a lot. I had to give up coffee (I developed a hypersensitivity to caffeine), and it hasn't been much of a problem since. I'm way rusty on the guitar - I've hardly ever played for the past two years. My fingers are crying and cursing me now - I have to find time for my first love again.
I actually prefer a little sweat on my fingers. Helps me move around the neck a bit better. They used to make this stuff called "gorilla snot" but I think that was more for drummers. (and apparently they still do? seems to have morphed into a hair gel)
That's actually part of the problem. Not only are my fingers slipping off the strings, the dampness is affecting my callouses, and I'm getting very deep blisters beneath. It's all a bit weird as it's only startied happening recently. Hope to goodness you're not right...never considered my coffee intake as it hasn't bothered me before. Something to think about.
I'm the total reverse. My fretting hand needs to be really dry. Different matter when I'm playing electric, as I use fret oil, but for classical I need less slide and more control.
Blisters? Ouch. Never gotten those. Are you playing more than normal? Or have you started playing again after your calluses have softened from a layoff? Check out some of the guitar forums. Here's the basic search, seems to affect bassists more, which isn't surprising: https://www.google.com/search?q=blisters+from+guitar+playing&ie=utf-8&oe=utf-8
I am but I usually play enough to maintain the callouses, so I don't have to go through the pain and aggravation if I do have a binge. I'll check that link because these blisters are what I'd expect from bass string girth, not a nice hand friendly, perfectly actioned, nylon stringed guitar.