Methocarbamol is used commonly in sport-horse practice to treat and manage sore backs and muscle strain. It sometimes is prescribed for preventive use in horses that are prone to exertional rhabdomyolysis. Methocarbamol is a CNS depressant and has secondary sedative-properties that may affect coordination and performance. Although oral methocarbamol is not FDA-approved for use in horses, it is a commonly used and accepted practice. 500 mg/tab. Brand may vary.