Rehydrate: Electrolyte Sports drink for Dogs REHYDRATE is designed to give canines a more effective hydration system than drinking plain water. The effervescent tablet that dissolves in water is formulated to replenish any lost electrolytes (i.e. sodium, chloride, potassium, etc.) due to aerobic activity. Also included are Vitamin C and other antioxidant minerals geared to promote general wellness. Each tablet is also flavored to enhance the palatability to promote optimum hydration and water intake. 10 Tabs per box.