Neuropathic pain is pain that develops as a direct result of injury or irritation to a nerve. Horses with injuries that involve nerve damage, horses that have had neurectomies and possibly some horses with back pain can suffer from neuropathic pain. Horses with injuries that involve excessive traction on their legs can also suffer nerve damage as it enters the top of the leg, causing them to have severe lameness and often sweating and skin temperature changes.
A case report from North Carolina State in the Journal of theAmerican Veterinary Association describes a pregnant Belgian mare that had colic surgery and was noted during recovery to not be using her left hind leg well. Within 1.5 days, she also developed severe pain that did not respond to the usual drugs. She was treated with gabapentin, orally twice a day, with rapid relief of her pain. After six days of treatment, she was weaned off the drug.
Gabapentin (brand name Neurontin) is a human drug that was initially developed as an epilepsy drug but has since been more commonly used to treat neuropathic pain.