It’s no secret that cats are mysterious. It’s part of their appeal. Cats constantly surprise us. As a feline practitioner, I’ve had many cat owners describe a scenario where their cat, relaxing on a couch or bed, suddenly sits up, gets a strange look in his eyes, frantically grooms his flank or tail, then darts across the room as if possessed by evil spirits.
It’s tempting to merely think of this as nutty cat behavior, but it may actually be signs of an enigmatic condition called feline hyperesthesia syndrome(FHS). The word hyperesthesia means extreme sensitivity to touch. Cats with FHS may show a variety of behavior changes, a prominent one being (as the name suggests) a heightened reactivity to being touched, most notably over the lower back and rump.
The behavioral manifestations of FHS can vary widely. Most affected cats become fixated on their tails. They may swish their tails back and forth, chase them, compulsively groom them, oreven attack and mutilate them. The skin along the back may twitch or ripple. In fact, this disorder is sometimes referred to as “rolling skin disease.”
Some cats will experience dramatic mood swings, with sudden bouts of hyperactive, aggressive, surprised or fearful behavior. During a bout of FHS, cats may show dilated pupils or get a strange look to their eyes, perhaps behaving as if they’re having hallucinations: seemingly following the movement of a spot or an insect that isn’t there, fleeing from an unseen adversary or staring vacuously into space. A few cats during an episode of FHS willvocalize, crying or meowing loudly. Although these episodes may happen spontaneously, they may be triggered simply by touching or stroking a cat along the spine.
In severe cases, the signs of FHS can progress to a seizure, with the cat falling over, salivating, his legs paddling. Cats of any age may be affected, although it’s more common in mature animals. Abyssinians, Burmese, Himalayans and Siamese are predisposed, although any breed can be afflicted. Every cat is different in terms of how frequently these episodes occur, from once every few days to every day to nearly constantly throughout the day.
The cause of FHS remains elusive. Some people feel that it may be some type of seizure disorder, as some cats will experience a grand mal seizure during or following a bout of FHS. The fact that some cats respond to antiseizure medication supports this notion. Other people claim that FHS may be a form of obsessive-compulsive disorder (OCD), with the obsession relating mainly to grooming. The compulsive nature of the self-directed flank and/or tail grooming, and the positive response in some cats to anti-obsessional drugs
supports this school of thought.
A possible hereditary tendency for FHS has also been suggested, as Oriental breeds are predisposed to the disorder. As with many behavioral conditions in cats, stress contributes to the symptoms of FHS.
There is no definitive test for FHS. A diagnosis is made based on the cat’s behavioral signs and by ruling out other medical disorders, especially skin disorders that may cause itchingand discomfort, and hyperthyroidism, which can cause hyperactivity, increased vocalization and other behavioral changes.
Treatment of FHS involves minimizing stress in the cat’s environment. Engaging in daily play behavior with the cat is thought to be beneficial. Actions that are known to trigger a bout of FHS, such as petting or scratching on the lower back or near the base of the tail should be strictly avoided.
In cases where bouts of FHS occur frequently and spontaneously, or where the symptoms are severe, medical therapy may be warranted. In my practice, I initially prescribe anti-obsessional drugs, with fluoxetine (Prozac) being my first choice. I have found it to be safe, effective and affordable.
If the cat responds poorly (or not at all), I will switch to an anti-convulsant drug, my first choice being phenobarbital, letting owners know that it may take two or three weeks before phenobarbital reaches effective levels in the bloodstream. Gabapentin, an anti-seizure drug that is also effective at reducing nerve-associated pain, is a recent addition to the arsenal of drugs that may be tried when treating FHS.
Fortunately, most cats with FHS respond nicely to environmental and pharmacological therapy, allowing them to once again lead a normal life. But if all medical treatments and behavior modifications fail to solve the problem, tail amputation needs to be considered. The cat may still show signs of obsession with the rear end and flank area, but amputating the tail will at least curb the mutilation, which can lead to infection. While I’ve never had a cat completely fail to respond to treatment, I’ve had some cats that required high doses of medication.
Providing a stimulating environment helps cats with FHS. A boring, monotonous environment is an underappreciated cause of stress in many cats.