Hartz UltraGuard Rid Worm Liquid for Cats A mild and effective method to remove roundworms (Toxocara Canis and Toxacaris Leonia) from cats and kittens. Includes 4 ounces of dewormer syrup For use on cats and kittens 8 weeks of age and older Easy-to-use syrup can be dropped directly into your pet's mouth or mixed into food. The first treatment should be repeated 14 days later Store product in a cool, dry place and avoid temperatures above 86F