You might need to look at your technique.
I used to get blisters whenever I played, my hands would cramp up and I would find it hard to get through a night's worth of playing.
About ten years ago, a local drummer introduced me to a technique called the "Gladstone" technique that literally changed the way I play. You can find it outlined best at Tiger Bill's website:
http://tigerbill.com/drumlessons/buildingmonsterchopsgladstone_part1.htm
http://tigerbill.com/drumlessons/buildingmonsterchopsgladstone_part2.htm
http://tigerbill.com/drumlessons/buildingmonsterchopsgladstone_part3.htm
There's way more stuff to check out as well.
Basically, it's all about staying relaxed while you play and letting the stick do it's share of the work. It took a while for me to get used to the concept (old habits are hard to break!) but now I can play just as hard and I never get blisters! I can go for twice as long and I don't feel anywhere as fatigued as I used to.
Check it out. It sounds cheesy, but it will change the way you play.
It won't happen overnight, but it will happen...!
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Yamaha drums :: Meinl cymbals :: Pro-Mark drumsticks :: Aquarian heads
http://www.myspace.com/funkengrooven