Narcolepsy and Cataplexy in Cats

Narcolepsy and cataplexy are rare in cats but have been reported. A cat with narcolepsy may suddenly fall into a deep sleep while standing, sitting, or eating, causing the cat to sway and fall over. A narcoleptic cat may also suddenly fall asleep while climbing, which can cause the cat to fall to the ground. A cat that is experiencing a cataplectic episode may run around excitedly and then suddenly collapse, unable to move but will still be looking around, perhaps meowing or whining, fully conscious. These conditions are not generally life threatening or even terribly worrisome, and can be treated with medication if diagnosed by your veterinarian.

Narcolepsy is a chronic brain disorder that is present in many types of animals, including human beings. Narcolepsy results from the brain’s inability to adequately and normally control the brain’s wake-sleep cycle, causing the narcoleptic to experience daytime tiredness and episodes of suddenly falling into a deep sleep, often at very inopportune times. Cataplexy is a similar brain disorder that often accompanies narcolepsy in animals and humans. Cataplexy is the sudden loss of muscle strength, which causes a loss of muscle control and usually results in collapse. This is different than narcolepsy, however, because during a cataplectic episode the cat remains fully conscious but is unable to move. These episodes often occur during or immediately after moments of great excitement.

Narcolepsy can be more difficult to diagnose in cats than in many other animals because of a cat’s natural tendency to sleep from 13-18 hours per 24 hour period, taking perhaps a dozen or more naps throughout the day. It will often take a pet owner repeatedly observing the following symptoms in their cat in order to cause enough concern to make an appointment with a veterinarian. 

• Excessive tiredness, which can be difficult to notice in cats
• Falling into a deep sleep while standing, sitting, walking, or eating
• Falling asleep while climbing, resulting in the cat falling to the ground
• Collapse and inability to move during or immediately after times of excitement

The causes of narcolepsy and cataplexy are not definitively known. These conditions rarely seem to run in families; most cases seem to be sporadic, occurring with no known family history of this brain disorder. In humans, studies have found a connection between narcolepsy and low levels of the neurotransmitter hypocretin, which promotes wakefulness. Also in humans, cataplexy seems to be caused by a low number of brain cells that produce hypocretin. Researchers believe that the low number of these cells is likely caused by an immune deficiency. Very rarely narcolepsy and cataplexy may be caused by a traumatic brain injury. Narcolepsy and cataplexy are so rare in cats that the veterinary research community has not devoted many resources to studying the condition in cats or comparing it to the condition in other animals. Most of the knowledge about narcolepsy and cataplexy comes from studies done on human and large animal subjects.

If the pet owner has repeatedly observed the symptoms listed above in their cat, causing enough concern to warrant an appointment with their veterinarian, the vet will likely do the following things to help her or him to make an accurate diagnosis:

• Thorough physical examination of your cat
• Blood tests to rule out other illnesses
• Listen to your descriptions of the symptoms you have observed
• Observe the cat’s behavior for an extended period of time
• Excite the cat in an attempt to cause a cataplectic episode that can be observed
• Ask you to make video recordings of episodes
• Ask you to keep a journal of when you observe episodes occurring in order to identify patterns or triggers
• Perform an MRI or other scans on the brain to rule out tumors or other neurological disorders or injuries that might be causing seizures or syncope, which is commonly referred to as fainting

Although narcolepsy and cataplexy may be troubling to you and to your cat as well, they are not, in and of themselves, life threatening or painful conditions for a cat. Dependent upon the severity of your cat’s condition and the level of treatment you are willing to undertake, your veterinarian may merely suggest that you keep observing your cat so as to observe whether or not their symptoms are becoming more frequent or severe. They may suggest this observation while also prescribing antidepressant medications that can affect the cat’s brain chemistry so as to lessen both the frequency and severity of attacks.

Both narcolepsy and cataplexy are chronic conditions that cannot be cured but may be treated and managed with medication and/or changes in the cat’s environment. The main goal of managing these conditions is to keep your cat safe from physical harm. A cat that is living with narcolepsy and/or cataplexy should likely be kept indoors in order to lessen the likelihood of a dangerous narcoleptic episode such as falling asleep while on a tree branch or while walking across the street and to prevent dangerous cataplectic events that might result from excitement caused by threats such as an aggressive dog, cat, or wild animal, which would render your cat unable to defend itself or flee. With guidance provided by your veterinarian, special attention from you, and possibly medication, your cat may be able to live a long, relatively normal life.