The Epsom Salt Poultice is for drawing out infection and soreness from hooves. To use, Apply Directly to Painful Muscles Tendons and Joints. Repeat as Needed For Relief of Soreness and to Relax Muscles. Can Be Covered with Cotton Or Wrap. Pack the Frog Or Abscessed Area and Cover.... (read more) May Be Used In Both Horses For Muscle Joint and Hoof Pain. May Also Be Used In Humans For Muscular Soreness. Product contains Epsom Salt - 60% Methyl Salicylate - Q. S.