Cataplexy Explained: Understanding its Nexus with Narcolepsy, Causes, Symptoms, Diagnosis and Treatment Options

The abrupt or sudden loss of muscle tone making you lose control is cataplexy and it can be associated with another condition, which is narcolepsy ⁽¹⁾. Cataplexy can resemble a seizure; however, it is very much different to that. Treatment of cataplexy consists of lifestyle changes and medication.

Cataplexy occurs when the muscles of the body significantly weaken or suddenly become limp without any warning. A person can experience cataplexy upon feeling a strong emotion, such as laughing, crying, feeling angry or grieving. A person suffering from cataplexy can feel as if they are losing control of their expressions and also find as if they are falling.

Narcolepsy is associated with cataplexy, which is a neurological condition causing extreme sleepiness during the day ⁽²⁾. The patient having narcolepsy can experience sudden episodes of falling asleep, even in the middle of an activity or a conversation.

Some of the other symptoms of narcolepsy are:

• Hypnogogic hallucinations or hallucinations before falling asleep.
• Sleep paralysis or feeling paralyzed as one is falling asleep.
• Hypnopompic hallucinations, which are hallucinations when a person wakes up in the middle of the night.

However, narcolepsy affects about 1 in 2000 people and people suffering from cataplexy associated with narcolepsy are even lesser ⁽³⁾. However, cataplexy can be very disturbing for your life causing complications by sudden loss of muscle control; more so if it is at the wrong time, such as when driving, during an office meeting, when playing sports etc.

If the patient has narcolepsy along with cataplexy, then it means that the brain doesn’t have sufficient orexin (hypocretin), which is a neuropeptide responsible for keeping the person awake and in controlling rapid eye movement of the sleep cycle ^{(1, 4)}. There are also other areas of the brain that control the sleep cycle and are considered to play a role in development of narcolepsy along with cataplexy.

Narcolepsy is not inherited in majority of the cases. However, about 10% of people having cataplexy and narcolepsy have close relatives with symptoms of these two conditions. Other causes and risk factors of narcolepsy with cataplexy are:

• Traumatic injury to the brain or head.
• Autoimmune conditions, where the immune system attacks the brain cells having hypocretin.
• Viral infections like swine flu (H1N1 virus) or getting a vaccine for the same.
• Tumors near areas of the brain responsible for controlling sleep.

If someone is suffering from narcolepsy, then the chances are high that they will also experience an attack of cataplexy at some point in life. However, not everyone having narcolepsy has cataplexy as a symptom.

Symptoms of cataplexy differ from person to person. Many individuals start experiencing their symptoms when they are in their teens or as young adults ⁽¹⁾. This happens when you are a freshman at college or at work or any other potentially stressful and new environment ⁽¹⁾.

Some of the symptoms of cataplexy are: neck muscle weakness causing the head to fall on the side; drooping eyelids; the entire body falling to the ground and twitching in the different muscles of the body without any cause.

Acute cataplexy is commonly misdiagnosed as a seizure; however, the difference being that the patient remains conscious and aware and remembers what occurs during the episode unlike in seizures where the patient does not remember anything. The cataplectic attacks are also different in duration where they can last for some seconds or can last for a few minutes.

Cataplexy tends to occur after the patient has experienced strong emotion and some of these emotional triggers are: happiness, excitement, stress, anger, fear and laughter ⁽¹⁾.

Not everyone suffering from cataplexy will have triggers and they also might not be consistent. Laughing can trigger cataplexy in some situations, but not always. Anger can also trigger a cataplectic attack, but not necessarily always or in necessarily in another patient.

Cataplexy can potentially be one of the first obvious symptoms in patients having narcolepsy. It can seem like a minor abnormality in the muscle, such as drooping of the eyelid or falling of the head because of weak neck muscles, which creates a confusion as to if the person is suffering from cataplexy or narcolepsy.

If your doctor suspects the patient had narcolepsy along with cataplexy, then the following tests are recommended for diagnosis ⁽⁵⁾:

Physical Exam:  A complete physical examination to check the general health of the patient to exclude other causes of the symptoms.

Written Evaluation: The patient is made to fill a written evaluation, such as the Epworth Sleepiness Scale or the Stanford Narcolepsy Questionnaire to learn more about the patient’s sleep habits and the severity of narcoleptic symptoms.

Sleep Latency Test: A multiple sleep latency test is also recommended where the patient is told to take short naps throughout the day with a gap of a couple of hours to check how quickly the patient falls asleep when taking the nap

Sleep Study: The patient is told to take part in polysomnogram, which is a sleep study that records all the activity occurring in the brain and muscles while the patient is sleeping.

Testing of CSF: Cerebrospinal fluid can be withdrawn and sent for testing to check for abnormal levels of hypocretin ⁽¹⁾.

Treatment for cataplexy as well as narcolepsy consists of medication and lifestyle changes. There is no cure for either condition; however, medications help in managing the symptoms and making the patient’s life easier.

Some of the common medications used for treatment of cataplexy (with or without narcolepsy) are ^{(1, 5)}: selective serotonin uptake re-inhibitors (SSRIs); tricyclic antidepressants and sodium oxybate (Xyrem) ⁽⁶⁾.

Medications for treating narcolepsy with cataplexy are ⁽¹⁾: modafinil to decrease the drowsiness and increasing alertness and stimulants resembling amphetamines to keep the patient alert.

Some of the side effects of these medications can be quite disruptive and consists of abnormal heart rhythm, nervousness and mood changes. There is also a risk of getting addicted to these medications.

The symptoms of cataplexy and narcolepsy occur abruptly without any warning and can be dangerous and fatal if the patient is operating machinery or driving a car. A cataplectic episode can also be dangerous where the patient is involved in any activity involving dangerous objects or heat, such as cooking or using sharp objects such as knives.

If the patient understands which emotions trigger these cataplectic attacks, then they can avoid situations where these triggers can occur, such as social gatherings where you might laugh hard or confrontational scenes where the patient can cry or get angry. It may be difficult for the spouse, family and friends to understand and adjust to your condition and this can cause strain on relationships and friendships.

Cataplexy can also cause difficulties at work where the patient cannot perform during these episodes.  Also having insufficient hypocretin along with certain choices in life can cause weight gain and obesity resulting in a different set of complications, such as heart disease, stroke and hypertension.

Cataplexy and narcolepsy both these conditions are disruptive and affect the daily life of the patient. It puts strain on any close relationships, personal or professional. However, with medications and lifestyle changes, cataplexy can be managed and after it gets under control, the risk of an episode while doing anything potentially harmful, such as cooking or driving also decreases. So, the outcome and prognosis of cataplexy are good and manageable.

Making some lifestyle changes greatly helps with the symptoms of cataplexy and narcolepsy and increase the quality of life of the patient.

• Inform your friends and relatives about your condition and how to identify the symptoms of an oncoming attack so they can help you cope with it.
• Always be aware of your surroundings, the terrain or objects around you which can harm you if you suffer from a cataplectic attack.
• Avoid driving as much as possible or have someone with you while driving.
• It is important to get consistent sleep as much as possible, as this will help you in battling and cutting down the risk for cataplexy episodes.
• Go prepared for situations where you know you will have to face possible triggers, such as situations causing strong overwhelming emotions. Always keep a chair close by just in case you need to use it.

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