iO Epsom salts, or magnesium sulfate, is becoming an increasingly common supplement and is also known as a laxative for horses. It?s also known to reduce equine obesity, and can lessen the risk of laminitis in animals prone to it during periods of strong spring grass growth. Magnesium plays an important role in nerve and muscle function, and horses deficient in this important element can show signs of nervousness, wariness, excitability, and muscle tremors. iO Epsom salts can also be used to ease joint pain in a horse. Soak its legs in a bucket of warm water to which you have added one cup of magnesium sulphate. This will help reduce the appearance of windgalls and the inflammation around a strained tendon or ligament. Older, arthritic horses will benefit from a 25-minute leg soak. iO Epsom Salts are also good for Insect bites, Wounds, Repellent, Laxatives, Fabric Softener and Conditioner in horses.