Making way in my quest!
Practical Horseman did an article called 'All Shook Up' in their April 2009 issue, it also has suggested a few treatments. They also have a website with further suggestions on treatments and devices. I had sent an email to the editor suggesting a treatment and recieved this email back:
"Thank you, Jolene, for the information. I have updated the page on EquiSearch with the info you sent on Capstar as well as a link to your own Web site. Good luck in your search for solutions.
Happy riding and reading!
Managing Editor, Practical Horseman"
She has referrenced and made a link to my website!
'Click Here' to view this Article.
Back in November I had received a very surprising email from an Equiwinner representative, Warren, through my postings on forums and on the Practical Horseman website that Stacey had published me on. Warren contacted me through the website form and wrote this:
We would be happy to send a course of Equiwinner to relieve Fox' s suffering from headshaking, free of charge. Please just let us have an address where the parcel can be sent. Best regards, Warren
To say the least, I was completely surprised and at first thought it was a weird scam or joke. So I wrote back:
Wow, I wasn't expecting a trial for free! Thank you very much, I've been investigating Equiwinner and a few other treatments and it always seemed that Equiwinner came out on top. I was surprised to read that there are no side effects which is a huge plus. I was looking to start her on that over the spring time and do four treatments as suggested on one of your pages, one for each season as it seems to help from what I've been reading about on severe cases.
She has been getting worse consistently and it's been hard to pin point her triggers.
My address is:
If you have any other information, testimonials and such I would love to read them and publish them to my site if your interested.
And again was delighted to get a response back from Warren confirming that yes he would be shipping me the Equiwinner via Airmail:
Thank you for your message. We are sending the Equiwinner airmail on Monday.
There are many testimonials on the UK and the Canadian distributor websites.
Also attached please find an article that appeared in Hoofbeats magazine.
Equiwinner has been very successful with headshaking, with the condition resolved in many hundreds of horses. So far as we know, Equiwinner is the only treatment that will completely and permanently clear the condition, rather than just supressing the symptoms.
Also, although we cannot say success is absolutely certain, the success rate is now over 90 per cent worldwide. The principal reason for failure is high blood sugar (usually horse overweight) as it is difficult to get the blood pressure optimum when the blood constituents are abnormal.
Best wishes for success with your horse.
I did infact receive Warren's shipment with the product from Equiwinner, I had been doing more research as Equiwinner was the choice I was leaning towards for Fox's first treatment to battle the Head Shaking.
As far as I can tell, the one thing that does effect the results of this product is when the horse is not in good working/physical condition. The blood sugar levels are higher when a horse is not consistently worked or is off work say for the winter months. Therefore I have been waiting till after the December craziness that is my job as well as wait till I got back from my vacation in early January so that I could dedicate a proper and consistent training schedule for Fox to ensure that she is in the right condition to start treatments.
I have also read that you can use 1 treatment per season to help combat the serious cases of Head Shaking, totaling 4 treatments for a 1 year time span. They also suggest this for not only the severe cases but also for horses with Head Shaking who are competing regularly to heavily throughout the year.
Warren had also sent me a link to frequently asked questions as well as a further link to asking somewhat more difficult questions so I will be posting back the questions that I have asked and the response I have gotten back. My questions will basically pertain to when the best time to start treatment is (ie: start of season, middle?) as well as up keep and if there are certain foods to avoid while on treatment.
I will be purchasing 3 other treatments of Equiwinner and do 4 for the year of 2010.
Keep your fingers crossed!
Issue Date: Compendium Equine
(Vol 4, No 7)
Photic Head Shaking
Bonnie R. Rush, Jason A. Grady
Head shaking is a behavior in which horses toss their heads, rub their noses, snort, and/or sneeze in the absence of obvious external stimuli. Some horses head shake with such violence that they are dangerous to the handler or rider.
In a 1987 review of 100 head shaking horses, the cause was undetermined in nearly 90% of cases. In 1995, Madigan and coworkers presented a series of seven cases in which head shaking was triggered by natural sunlight, and darkness provided relief from the condition; this disorder is called photic head shaking. Photic head shaking horses are suspected to experience a burning sensation or tingling of the muzzle (neuropathic pain) in response to bright sunlight.
The mechanism of photic head shaking may be similar to photic sneezing in humans, in which exposure to bright light triggers sneezing episodes. Photic sneezing in humans is a heritable, nonallergic disorder. Photic head shaking may represent a form of referred pain in which stimulation of one of the cranial nerves enhances irritability of the other—in this instance, optic-trigeminal summation. This may be associated with convergence between optic and trigeminal tracts in the brainstem. Therefore, neuropathic pain is the most plausible explanation for the signs associated with photic head shaking.
Bright sunlight is the most common trigger for neuropathic head shakers, but other stimuli, including specific feeds (as in gustatory head shaking), may also serve as a trigger for infraorbital nerve irritability. Therefore, disorders other than neuropathic pain should be evaluated to eliminate other causes of this behavior. In some horses, the triggering stimulus cannot be identified; however, the head shaking seems to be characteristic of neuropathic pain, and affected patients respond to medical therapy.
The condition affects adult horses. The mean age of onset is 7.5 to 9.2 years. However, it has been documented in horses younger than 5 years.
No breed predilection.
Geldings are overrepresented. Affected mares should be evaluated for ovarian dysfunction. The absence of testicular or ovarian hormones may play a role in the pathophysiology.
Clinical signs are often seasonal, abating during the winter and returning in the spring.
The behavior is exhibited at rest and during exercise. Violent head shaking is common at the beginning of exercise.
Affected horses attempt to avoid direct sunlight by seeking shade or hiding their heads in unusual places.
Photic head shaking may begin after an upper respiratory tract infection.
Horses may not exhibit the behavior during the examination; therefore, the owner should be asked to make a videotape of the head shaking before the appointment.
Physical Examination Findings
Sudden, violent, jerking movements of the head in the absence of obvious external stimuli.
Characteristic quick vertical flips or jerking movements (as if stung by a bee on the end of the nose) may be interspersed with horizontal and rotary activity.
Affected horses often snort, sneeze, and rub their noses.
Ophthalmic, otic, and oral examinations should be performed to rule out other causes of head shaking.
Findings are unremarkable in photic head shakers.
Horses with head shaking due to causes other than sunlight usually demonstrate intentional head tossing rather than rapid, vertical flips that resemble a reaction to a bee sting.
Complete blood count and serum chemistry analysis findings are unremarkable.
Endoscopic examination of the upper respiratory tract (including guttural pouches) and radiographic examination of the skull should be performed in all horses with head shaking to rule out temporohyoid osteoarthropathy, a foreign body, or traumatic injury. The results are unremarkable in horses with photic head shaking.
Other Significant Diagnostic Findings
To determine whether the behavior is induced by natural light, ideally, the clinician should subject the horse to the following: direct sunlight, blindfolding, the outdoors at night, and the application of dark eye lenses (FIGURE 1) in direct sunlight. The cessation of clinical signs during protection from direct sunlight indicates that light is a stimulus for head shaking.
Bilateral infraorbital nerve block (FIGURE 2; 10 mL of mepivacaine over and within the infraorbital canal) should be performed in horses with characteristic head shaking that does not respond to medical management. If nerve block results in the abatement of clinical signs, the diagnosis is confirmed.
Bilateral posterior ethmoidal nerve block (FIGURE 3; 5 mL of mepivacaine) using a 7-cm, 19-gauge spinal needle: the needle is inserted below the zygomatic arch and directed rostrally and ventrally toward the upper sixth cheek tooth (approximately 5 cm; FIGURE 4).
See BOX 1.
Summary of Diagnostic Criteria for Photic Head Shaking
Negative findings from otic, ophthalmic, oral, endoscopic (the upper airway, including the guttural pouches), and radiographic (skull) examinations.
Demonstration of sunlight-induced head shaking (sunlight may not be the only trigger for neuropathic head shaking).
Favorable response to a 7-day course of cyproheptadine and/or carbamazepine (see below).
Favorable response to bilateral infraorbital or posterior ethmoidal nerve block in horses that do not respond to cyproheptadine.
Cyproheptadine is an antihistamine and serotonin antagonist with anticholinergic effects. The mechanism of action of cyproheptadine in treating photic head shaking is unknown.
Administer a 7-day course of cyproheptadine (0.3–0.6 mg/kg PO q12h) to determine response to therapy.
Horses that respond favorably should be treated with cyproheptadine during the season in which they exhibit head shaking.
Adverse effects include transient lethargy, depression, or anorexia.
Carbamazepine (3–4 mg/kg PO q6–8h), which is labeled for treating trigeminal neuralgia in humans, may be administered alone or with cyproheptadine in horses that fail to respond to cyproheptadine alone.
Melatonin (15–18 mg PO q24h administered between 5:00 and 6:00 pm) has reduced clinical signs in some horses.
Topical EMLA Cream
Topical EMLA cream (AstraZeneca; lidocaine 2.5% and prilocaine 2.5%) may provide transient relief when applied to the muzzle. Cover area with plastic wrap (make holes for nostrils). Leave on for 45 minutes.
Cyproheptadine (as described above).
Magnesium supplementation (Quiessence, Foxden Equine, Stuarts Draft, VA).
— Increases threshold for nerve depolarization and may reduce irritability of trigeminal nerve.
— Administer 2 oz q24h PO.
— Increase to 4 oz q24h PO if no improvement.
— Evaluate serum magnesium after 2 wk, then once monthly.
Spirulina Wafers (Springtime, Inc, Cockeysville, MD).
— The mechanism is unknown, but they may increase the threshold for nerve depolarization and decrease irritability of the trigeminal nerve.
The use of a full-face net (covers ears to muzzle) or fly fringe or netting over the muzzle has reportedly been effective in controlling signs of head shaking. It is believed that the net or fringe over the muzzle provides a counterstimulant that may reduce responsiveness of the trigeminal nerve through receptor inhibition or adaptation.
A commercial face mask with eye protection can be applied to control clinical signs when the horse is saddled or turned out during daylight (FIGURE 1).
Bilateral infraorbital neurectomy is a salvage procedure for cases refractory to medical therapy. Surgical candidates must demonstrate a consistent response to serial infraorbital nerve blocks. Infraorbital neurectomy has been shown to be effective in eliminating signs of head shaking. However, clinical improvement is inconsistent and often only temporary. Postoperative complications may include nasal pruritus (common, temporary), reinnervation, and neuroma formation.
Bilateral sclerosis of the posterior ethmoidal branch of the trigeminal nerve is induced via perineural injection (5 mL) of 10% phenol in almond oil. In an anesthetized patient, insert a 20-cm styletted needle into the infraorbital canal to the level of the maxillary foramen; confirm needle location by fluoroscopy.
In a recent study on caudal compression of the infraorbital nerve in 24 horses, 16 of 19 horses had a successful outcome.1 The procedure requires specialized equipment, and the authors report that the technique needs refinement.
Horses should respond to cyproheptadine within 7 days.
If head shaking is well controlled, the dose of cyproheptadine may be decreased to 0.12 mg/kg PO q12h.
In many cases, medication may be discontinued during the winter.
If sunlight has been identified as the stimulus of infraorbital pain, reduced sunlight exposure is indicated for untreated horses or horses that do not respond to medical or surgical management. Affected horses can be turned out at night or during overcast days. If turned out during full sunlight, affected horses should have protection from the sun via a three-sided shed, trees, or a commercial face mask that provides eye protection.
Milestones/Recovery Time Frames
Approximately 70% to 80% of photic head shakers respond favorably to cyproheptadine. Some horses may respond initially but become more resistant to therapy.
More than 80% of horses respond favorably to carbamazepine alone or in combination with cyproheptadine.
Relief from head shaking may be observed within 48 hours of initiation of therapy.
Clinical signs typically recur 24 hours after discontinuation of medical therapy.
Bilateral Infraorbital Neurectomy
Approximately 30% to 40% of photic head shakers improve after this procedure.
Careful case selection (consistent response to infraorbital nerve block) may increase the likelihood of a positive postoperative outcome.
Clinical signs of head shaking completely resolve in 25% to 30% of horses with the use of a nose fringe or netting that applies pressure to the skin over the muzzle.
Administration of antihistamines, corticosteroids, or NSAIDs is unrewarding.
Intradermal skin testing followed by allergen-specific hyposensitization therapy is unsuccessful.
Response to cyproheptadine within the first 7 days of treatment.
Failure to respond to recommended therapies.
1. Roberts VL, McKane SA, Williams A, Knottenbelt DC. Caudal compression of the infraorbital nerve: a novel surgical technique for treatment of idiopathic headshaking and assessment of its efficacy in 24 horses. Equine Vet J 2009;41(2):165-170.
Updated by the authors and reprinted with permission from Standards of Care: Equine Diagnosis and Treatment 2001;1.1:1-4.
To Learn More
Understanding Behavior: Head Shaking (November/December 2008).
To see a video of a horse with head shaking, go to the Web exclusives at CompendiumEquine.com.