I suffer from hyperhidrosis (excessive sweating), which at times makes knitting very difficult. Once my hands start sweating, they sweat terribly and I mean TERRIBLY…lol…Usually when my hands begin to sweat I have to stop knitting because the yarn becomes wrapped too tightly around my fingers while trying to knit, and, if I’m making something for someone else, well, I don’t want my nasty hand sweat absorbed by the yarn…lol…Recently I tried my own ‘remedy’ (if it can be called that…lol); I took a pair of winter gloves, chopped off the fingers halfway then wrapped medical tape around my pinky finger to keep the yarn from wrapping too tightly around the glove…Does anyone else have this problem and if so, how do you keep hyperhidrosis from interfering with your knitting?
Do you think that different types of yarn make a difference, for example does wool make it worse than cotton, or the needle material (metal, bamboo, resin), or do you think is it the knitting process itself that brings it on? Maybe trying a different knitting technique, like trying continental versus English (or vice versa) might change how you hold the yarn. I suppose it might take a bit of experimenting to see what will work best for you.
I wonder if cotton gloves or fingerless gloves might help? I don’t know if they’d be hard to knit in or not… 
I have the same problem!
I like to work with a fan on to help keep my hands dry.
Other things I have tried: I got some 3/4 finger compression gloves from a medical supply company. Because they’re lycra/nylon, they don’t get soaked like cotton gloves would, and they really reduce friction problems, even when damp. There is enough coverage from the 3/4 finger version to allow the yarn to flow relatively smoothly through the crook of my pinky and over my forefinger, but in hindsight, I wish I had gotten the full finger version because I have unintentionally felted wool yarn just because my fingertips were sweaty when I worked it. :oops:
On the downside, the gloves started to come apart at the seams after relatively little use. Maybe a different brand would be more durable, I don’t know. Getting the full finger style might help as well since the main points of failure occurs at the seams around the fingertip “hem.” (It is basically serged together so I hesitate to call it a hem.)
I have also tried clover yarn guides. They are essentially plastic rings that you can wear on your finger that multiple strands of yarn can pass through. It’s made for color work (to keep the different colors separated), but I just used it with one skein. I bought two so I could wear one on my pinky and another on my pointer finger. I stranded the yarn back and forth through the guides to adjust the tension. (Just on the pinky one.) The main problem was comfort, as you can probably imagine. They also are pretty flimsy.
I guess my advice would be to try the fan first. Let it blow directly on your hands. Keep a towel close (or just use your t-shirt like me) for intermittent blotting as needed. If that’s not sufficient, try the gloves. They really do help. I think the nylon aids evaporation, and keeps your hands cooler, especially if used in conjunction with a fan. I thought I might not be able to knit because of my little problem, but I’ve managed to adapt. I’m sure you will too. 
ETA: Here’s a link to the gloves I got. Like I said, they could be more durable. But it gives you an idea. They sell the full finger as well. Shipping was fast.
Oh awesome, thank you! Yeah, it’s a bit annoying trying to knit with those bulky winter gloves…lol…And, unfortunately my problem is so severe, a fan doesn’t cut it…Sometimes I have to just end up taking a cool bath…And gardenmommy, unfortunately again, it doesn’t matter what type of yarn or needle I use…With this crappy condition, I sweat for absolutely no reason at all…I don’t even have to be knitting…Sometimes just thinking about my hands sweating makes them start to sweat! I don’t completely understand it (hyperhidrosis)…I’ve suffered from hyperhidrosis for as long as I can remember, but it hasn’t been until just recently the condition began getting media attention and I finally learned what was wrong with me…lol…And back to jane, I TOTALLY know about keeping the towel or paper towels handy! LOL! And even just the wiping on the shirt…Only thing I hate about wiping my hands on my shirt is any lint stuck to my shirt gets stuck to my sweaty hands…hahaha…If you haven’t seen this site yet, I found it EXTREMELY helpful in better understanding hyperhidrosis: http://www.sweathelp.org/English/
I sweat “on demand” too. I actually find that it comes in useful when I need to do a felted join. No kidding! :roflhard:
I will definitely check out that site. I did a lot of research a while back, but haven’t kept up with recent developments.