GU Hydration Drink Tabs are reformulated with Xylitol to help reduce gastrointestinal distress when compared to sorbitol. Sodium, the primary electrolyte lost in sweat, helps maintain water balance. Use GU Hydration Drink Tabs before, during and after exercise to hydrate and replenish electrolyte levels. Electrolytes maintain system balance and aid in optimum hydration. GU Hydration Drink Tabs can be dropped into water to add essential electrolytes, great flavor, and light effervescence to your water to keep you hydrating.