Some may say that this is your horse’s way of saying ‘neigh’ to whatever it is that you’re asking them, but truth is, head shaking can be an indicator of many things. This behavior can be sometimes done out of boredom, or to deter flies, but sometimes it can be an indicator of a medical problem. If you notice your horse is shaking his/her head more often than normal, without an obvious presence of a flying, buzzing pest, it may be time to call your vet.
If your horse is chronically shaking their head, your vet will probably look for signs of the following conditions:
- Sinus infections
- Dental conditions – such as broken teeth, or dental diseases
- Ear infections, ticks, or foreign bodies
- Tumors in the head, ears, neck or nose
- Abnormalities in the neck, throat or guttural pouch
- Signs of foreign bodies stuck in the ear, mouth, or nasal cavities
If your horse is shaking their head mostly up and down, and in sudden, jerking motions that make it difficult to ride, he/she may be experiencing a more serious condition.
In 1995 a condition called Photic Headshaking was identified. Affected horses are believed to experience a burning or tingling sensation in their nostrils when they see sunlight- similar to how looking towards a light might help induce sneezing. However, with this condition, there is no sneeze or relief that comes with a sneeze.
Similarly, horses can also have the same sensation triggered by specific feeds (called gustatory head shaking), or have the sensation with no specific triggers. Some believe that the sensation they experience is better described as a neuropathic pain, which is caused by a sensitive nerve firing rapidly.
Some of the major downsides of treating head shaking conditions are that the drugs used reduce shaking and control nerve pain vary in their success, and often tend to have short term results. Many of these drugs are not allowed for horses who compete in show and on the racetrack. Typically, oral antihistamines are used and they have a 60% success rate, at the cost of making the horse somewhat drowsy.
For horses with Photic Headshaking, some will use a net or a mask with ultraviolet light protection. These go over the muzzle, or the eyes to block light, and prevent the trigger of the pain. Treatment plans that have the highest levels of success usually include a combination of reducing sunlight exposure by using muzzles/mask, creating shelters for horses so they can have a place to go and avoid the light, and the aforementioned medications.
Additional treatments include making sure your horse’s diet is high in magnesium, which helps regulate the horse’s pH level and therefore also reduce excessive nerve firing. Alfalfa is a great resource of natural magnesium, and horses tend to love it. If your horse doesn’t like alfalfa, over the counter supplements are also effective.
A study completed at UC Davis found that magnesium supplements reduced headshaking significantly in horses that were previously shaking to aggressively to be safely ridden. The horses studied in their research now have stopped shaking completely. However, experts caution to monitor magnesium levels when giving these supplements, to prevent overdosing.
Beckstett, A. (January 4, 2019) “Headshaking in Horses: A Sensitive Matter.” The Horse. https://thehorse.com/139413/headshaking-in-horses-a-sensitive-matter/
Anonymous. (October 25, 2021). “Equine Internal Medicine: Headshaking.” Kansas State University Veterinary Health Center. https://www.ksvhc.org/services/equine/internal-medicine/headshaking.html#:~:text=Horses%20with%20photic%20headshaking%20are,into%20sunlight%20triggers%20sneezing%20episodes.