Have you ever seen a cat suddenly stop what they’re doing, freeze for a moment, then jump straight up into the air and take off running like a hellhound was after them?
For most cats, this is pretty common behavior – it’s simply a way to burn off excess energy or initiate play. But for some cats, this behavior can be part of a disorder known as “Feline Hyperesthesia Syndrome”, a rare medical condition that affects the brain and causes bizarre and frustrating symptoms in cats.
Feline Hyperesthesia Syndrome, or FHS, can cause such severe and dramatic changes in a cat’s behavior that some owners swear their poor cat is possessed. It can affect cats of all ages, but it usually appears for the first time in afflicted cats between the ages of 1 and 5 years.
Called “twitchy cat syndrome”, “rippling (or rolling) skin syndrome”, or more technically “atypical neurodermatitis”, FHS is generally thought to be either a form of epilepsy or a type of obsessive-compulsive disorder. Another theory suggests that it has a genetic component (since it’s more common in Siamese, Burmese, Abyssinian, and Persian cats) that’s triggered by chronic stress and anxiety. Recently, research experts have suggested that FHS is caused by a problem with the electrical activity in areas of the brain that control emotion, grooming, and predatory behavior.
The word hyperesthesia means “abnormally increased sensitivity of the skin.” Although no one knows for sure what causes Feline Hyperesthesia Syndrome, one thing we do know is that the poor cats who suffer from this disorder appear to be tormented by stimuli or sensations from which they can’t escape.
Symptoms of Feline Hyperesthesia Syndrome
Generally, cats with FHS will suddenly stop what they’re doing, look startled, and their tail will start swishing back and forth. They typically swing around towards their tail as if something is biting them on the back end. The muscles of the lower back often twitch, causing the skin to appear as if it’s rippling. Some cats will begin frantically licking or biting the skin around their tail, then take off running as if they’re trying to escape from whatever sensations they’re experiencing.
The video below shows a cat apparently in the midst of an episode of FHS:
Other symptoms of Feline Hyperesthesia Syndrome include:
- Dilated pupils
- Staring into space with a strange expression
- Loud, persistent meowing
- Self-mutilation, including pulling out clumps of hair and/or biting their own skin
- Sudden mood swings (often from extremely affectionate to aggressive, hyperactive, frightened, or depressed)
- Apparent hallucinations, resulting in chasing things that aren’t there, or running away from an imaginary threat
- Fixation with the tail, including tail chasing or vicious attacks directed at the tail (these can result in serious self-inflicted wounds, some bad enough that they require a portion of the tail to be amputated)
- Extreme sensitivity to touch, especially down the back and around the tail area (many cats with FHS experience episodes immediately after being stroked or petted along the spine)
- Frantic self-grooming directed along the flanks or tail (often leads to patchy hair loss)
- In some cases, drooling and uncontrolled urination
It’s very common for cats to experience seizure-type behavior (falling over, leg-paddling, drooling, or vocalizing) immediately after an episode of FHS, which supports the theory that it may be related to epilepsy.
Episodes of FHS can occur daily, every few days, or weekly, while some cats suffer with bouts almost continuously for days on end. During an episode, it can be very difficult to distract the cat or try to help in any way, making it traumatic and extremely frustrating for cat parents.
Since there’s no definitive test for Feline Hyperesthesia Syndrome, it can only be diagnosed by ruling out all other possible causes of the behavior. Cats in general are very sensitive to begin with, and many of the symptoms of FHS can be seen with several other health disorders that affect the skin, muscles, and nervous system, so several tests are usually needed to make sure there are no other underlying health conditions that could be causing the symptoms.
Other conditions that need to be crossed off the list before making a diagnosis of FHS include:
- Flea allergy dermatitis (itching of the skin and hair loss due to a cat’s allergic reaction to flea saliva)
- Fungal skin infections, such as yeast or ringworm
- Pinched nerve or a slipped disc
- Nutritional deficiency
- Mite infection
- Hyperthyroidism (too much thyroid hormone in the bloodstream)
- Toxin exposure
- Pain associated with abscesses, bite wounds, or impacted anal sacs
- Neurological issues such as brain tumor, head trauma, or infection of the brain
If a veterinarian suspects Feline Hyperesthesia Syndrome, he or she will do a thorough examination and perform several diagnostic tests to rule out any other medical issues. These tests can include blood work (chemistry panel, complete blood count, and thyroid test), skin tests, and/or x-rays. The vet may refer the patient to a neurologist (a specialist in everything related to the nervous system) or a dermatologist (skin specialist).
If you suspect your cat may be suffering from FHS, one of the best things you can do prior to your vet visit is to videotape your kitty during an episode and take the video with you to your appointment.
Treating Feline Hyperesthesia Syndrome
Address The Stress
If your cat is diagnosed with FHS, the first step in treating it is to reduce stress or anxiety as much as possible. Things that can trigger severe anxiety in cats include changes in schedule, moving to a new home, adding or losing a family member (including other pets), and aggression amongst other cats in the household. Other triggers may be something as simple as rearranging the furniture in the house, or boredom caused by the cat not getting enough mental stimulation.
Providing consistency in their daily routines, giving them plenty of opportunities to “be cats” (by providing places to climb, sleep, scratch, and hide), and making them feel safe are some of the best ways to reduce anxiety in cats.
Other tips for reducing stress include:
- Playing with your cat daily to give him both mental and physical exercise (feather toys on a wand work well for this).
- Providing interactive toys that can also be used by your cat when you’re not with him, such as puzzle feeders, ball tracks (which contain a ball inside a circular track), or any other toy that moves or interacts with him when he plays with it.
- Hiding dry treats around the house so he has to hunt for them.
- Feeding at least twice a day on a regular schedule.
- Making your home more cat-friendly by adding window perches, kitty condos (which provide vertical territory for cats), fish tanks, scratching posts, cat trees, and cat shelves (a series of staggered shelves mounted to the wall that create a kitty highway above the ground.)
Although there are currently no FDA-approved medications for treating Feline Hyperesthesia Syndrome, there are existing medications that can help reduce the severity of symptoms.
One class of drugs that seems to be particularly helpful for kitties with FHS are serotonin-enhancers. Serotonin is a neurotransmitter in the brain that helps stabilize mood, reduce aggression, and counteract obsessive-compulsive tendencies. Prozac®, Clomicalm®, Paxil®, and Zoloft® are all potent serotonin-enhancers.
Since FHS is also thought to be related to epilepsy, some vets prescribe the anti-seizure medication phenobarbital, which can be combined with other drugs used to treat FHS for a customized treatment protocol that is unique to each cat. Gabapentin, another anti-seizure medication that’s also used to treat nerve pain in humans, is also showing great promise for treating FHS in cats.
The goal of drug therapy is to find a balance where the cat is not sedated, but still experiencing as few bouts of FHS as possible. Once that happens, the dosage can be gradually reduced until the cat can be weaned off the drug(s) completely. However, some cats with FHS may require lifelong medication.
Acupuncture and massage therapy are additional treatment methods that are gaining favor in the veterinary community for treatment of FHS. It’s thought that these are effective by helping to reduce stress and nervous system overstimulation.
Not Just “Psycho Kitties”
Feline Hyperesthesia Syndrome it not a life-threatening disorder, but for the cats who experience it, it can dramatically impact their quality of life. Even though once it appears it doesn’t tend to progress or get much worse, FHS can put affected cats at risk for infections from scratching and biting at their own skin. And as you can imagine, the mental stress of constantly feeling tormented by a force from which they can never escape must be incredibly frustrating for them!
If you suspect that your cat may be suffering from FHS, please don’t hesitate to discuss it with your veterinarian. Although FHS is not considered completely curable, with stress management techniques and the right use of medication, it is possible to manage it and give your kitty a happy, comfortable life.
Have you ever seen a cat with Feline Hyperesthesia Syndrome? Please tell us about it in the comments below!