It sounds like dyshidrotic eczema. This is a mild and nonallergic condition that prodcues little bubbles on the fingers and palms. The cause is unknown. If it isn't bothersome, you don't have to treat it, but if it is troubling you, your doctor can prescribe a cortisone-containing cream to heal the blisters faster when they come. Prevention, however, is not possible so far as I know.
Best.
Dr. Rockoff