If you see your cat shaking his head frequently, it's a symptom of a medical issue that could be caused by a number of health conditions ranging from minor to serious. Whether your cat's head tremors are caused by ear mites, an infection, or a critical issue such as infectious peritonitis, it's vital to seek veterinary treatment.
Ear infections and parasites
Cats may not have as many ear problems as dogs, but some kitties occasionally suffer from ear infections or ear mites. The trouble with determining which is causing your cat to shake her head is that the symptoms of both are similar. Newport Harbor Animal Hospital says cats respond to the pain and discomfort of ear infections by shaking their head and scratching their ears. There may be debris or fluid in the ears that they want to remove. You may notice an odor emanating from the ears and/or a black or yellow discharge.
Cat shaking head due to oral problems
Because the ears and nose are closely connected, a problem in your cat's mouth can cause him to shake his head. VCA Hospitals explains that problems from dental disease in cats are often hidden until an x-ray is taken. Signs of an oral problem could include your cat twitching his head and drooling along with jaw chattering or pawing at his mouth. You may see him avoiding food or chewing or swallowing with obvious discomfort. Bad breath odor is also a sign of a cat with a mouth or dental problem.
Tumors on the pancreas
Part of the pancreas's job is to secrete insulin, but when a tumor interferes with the normal function of the pancreas, the resulting condition is called insulinoma. The condition causes the pancreas to overproduce insulin and results in hypoglycemia, with head shaking being one of the typical symptoms. AnimalPath.org says neurological signs such as seizures are common along with general weakness, which may lead a cat to simply collapse.
Feline infectious peritonitis
Typically, the cause of a cat shaking her head is minor and easy for the vet to treat. One of the more serious diseases that causes head shaking and bobbing in cats is feline infectious peritonitis, or FIP. This is a viral infection. The Cornell Feline Health Center says it's rare for a cat who is an "only child" to get FIP, but it can spread throughout multiple-cat environments, such as kennels and catteries.
The signs that indicate FIP include mild upper respiratory symptoms, such as sneezing, watery eyes, and nasal discharge, while others may experience mild gastrointestinal signs, such as diarrhea. Other signs can include loss of appetite, weight loss, depression, fever, and difficulty breathing caused by fluid accumulating in the abdomen.
The disease causes neurological problems in approximately 10 percent of the cats it affects, causes cat head tremors, and can cause seizures too. Until recently, FIP was considered to be a nontreatable disease, but some new anti-viral drugs may help.
Devon Rex myopathy
If your kitty is a Devon Rex, he may be genetically predisposed to a condition known as Devon Rex myopathy, sometimes called spasticity. Vetstream explains the hereditary condition as general muscle weakness accompanied by head bobbing, carrying the head low, and a "dog-begging" posture. There is no treatment for this condition. Because of the head bobbing, feeding a cat with this condition from a platform where the head is kept up can help prevent choking, which is an unfortunate side effect.
Since this is a congenital condition, it often makes its appearance early in a Devon Rex cat's life, between 3 and 23 weeks (5 to 6 months) of age. Progression is usually slow, and while some cats can go on with a comfortable life, other cats are highly affected.