If you find your horse on the ground and his legs are paddling as if he is running, his eyes are rolled back and his head and neck area are stiff - then shortly afterwards your horse's breathing becomes labored and shallow, he acts depressed and acts as though he can not see, your horse probably just experienced a seizure. Seizures in horses are not common, however seizures are a common reaction to some serious very types of illness.
A seizure is caused when the neurons in the brain emit a huge electrical discharge in response to a stimuli, that stimulating factor is usually a disease or symptom of disease. The main reasons for a horse having a seizure will fall into five main categories: abnormalities in the brain tissue of the horse, a defect such as a tumor, trauma -especially to the head area, metabolic abnormalities such as lack of water to the point of dehydration and then allowing the horse to rehydrate too quickly and the ingestion of toxins.
Some foals, and this occurs in Arabians more than any other breed, have seizures for no discernible reason, generally these type of seizures are outgrown. A less common reason for seizures that doesn't fit into a category is when an injection goes awry. Accident injection of certain drugs into the carotid artery in the neck of your horse can cause seizures. Make sure an experienced veterinarian does all injections.
Treatments for seizures are usually able to get them under control as they address a specific illness the horse is having. Phenobarbital is the most common drug used to fight seizures in horses. If your horse is having a seizure, get out of the way. It can be alarming to watch your companion flailing, but you cannot control a horse that on the average weighs in at over 1,100 LBS and you're risking injury by being too close.
After the seizure, comfort your horse and contact your veterinarian immediately. Seizures can be almost completely be controlled through elimination of environmental causes and drug therapies.






