My horse suffers each spring and summer from something that causes her to snap or toss her head and sneeze or snort/blow out through her nose very strongly and in succession. Sometimes she even rubs the inside of her upper lip on the ground. She doesn’t seem to have any control over the head snapping and does it even when I ride. In the winter these symptoms completely disappear. My vet says it has to do with air particulates/dust/pollen in her nasal passages. Do you have any ideas on how to manage this condition? – LK, Rhode Island
Your horse appears to be displaying some signs of what’s known as “headshaking.” Here is a more complete list so you can see how closely what you describe fits the syndrome:
- Flipping the head up and down in a vertical plane
- Snorting and sneezing
- Raising the upper lip
- Rubbing the muzzle on the ground and other objects
- Wiping or striking the face with a foreleg
- Anxious facial expression
You’ve already taken the appropriate first step– contacting your veterinarian. Now it’s time for a thorough physical examination. Sometimes horses that shake their heads do have a problem in their ears or other places that can be treated and the shaking goes away. Other times, no physical problems can be found and the horse is dubbed a “headshaker.” Your veterinarian will carefully examine the eyes, mouth, head and neck, and perhaps even take an X-ray of the skull to check for fractures. Other possible tests include “scoping” or using an endoscope to visually examine the guttural pouches and upper respiratory tract.
If there’s no obvious reason for your horse to have pain or discomfort, your veterinarian may perform a test to determine if bright light is a trigger factor. Owners of headshaking horses often report that signs are worse in broad daylight, which is why you may notice signs primarily in the spring and summer. That is, when a horse is ridden indoors or at night, there is very little headshaking. But when the horse is worked outdoors in bright sunshine with the same tack, rider and level of exercise, the horse shakes its head or performs one of the other signs in the list above. The theory is that headshaking is a photic, or light-stimulated, response. Much like some people sneeze when they see a bright light, some horses headshake. This may have to do with stimulation of a nerve in the face called the trigeminal nerve. If stimulation of this nerve in horses is anything like stimulation of the nerve in people, experts believe horses feel a tingling, itching or burning sensation in their muzzle.
As you’ve probably figured out, keeping a journal of exactly what your horse does and when he does it can be very helpful in figuring out WHY he does it. And if you can figure out why he does it, you may be able to prevent it. For example, if you and your veterinarian determine that light does indeed provoke his headshaking, then you may want to ride him inside during sunny days or work him in the evenings. Or you may want to try a special fly mask that blocks UV rays or extends past his nose. Also, nose nets that just cover the muzzle have been shown to help many horses, probably because they physically touch the part of the horse that feels “funny” and distracts them from the nuisance. Sometimes wind or moving air can trigger headshaking so covering the nose with a long fly mask or nose net is helpful for this reason.
While there are no medications that specifically treat headshaking, some horses have improved on the pharmaceutical cyproheptadine. Lysine, carbamazine and fluoxetine have worked on other horses. Antihistamines, steroids, NSAIDs have not shown any benefit. Owners have also tried acupuncture, chiropractic, homeopathy and other remedies, usually unsuccessfully. You may want to talk to your veterinarian about using melatonin, lysine or topical anesthetics. Finally, don’t be afraid to make changes in your tack or training methods, as some horses have improved when switched from a bit to a bitless bridle, and others have been able to be reconditioned or retrained not to headshake. I do want to make the point that if your horse is a true headshaker, this is an involuntary response and not something he should be punished for. Your job is to patiently and systematically eliminate any potential sources of irritation in the hopes the behavior isn’t triggered.