Spinal anesthetics and analgesics in the horse

In the past 10 years, there have been many recent advances in spinal techniques in horses, both epidural and subarachnoid, to identify drugs or drug combinations that have sensory effects without motor nerve paralysis, thus providing pain control without these horses becoming recumbent. Opioids, alpha-2 agonists, dissociative drugs, and others have been investigated. Many of these drugs, which have serious side effects when injected systemically in horses, have been shown to have useful analgesic effects when injected spinally. Morphine-like opioids have the greatest potential for spinal use as they produce long-lasting analgesia without motor effects. Often the doses used spinally are significantly lower than those needed for systemic effects.