Kleine-Levin Syndrome – Diagnosis, Causes, Treatment

Kleine-Levin Syndrome

Sleep is one of the essential functions of the human body. Even though it is still a mystery, we know that rest supports the growth and development of the body. This is why a newborn child sleeps for more than 18 hours a day. But as it gets older, the sleep requirements diminish. An average teenager sleeps for 10 hours a day, and an adult (18-64) needs 6 hours of sleep

Unfortunately, this is not the case with everyone. A combination of hypothalamic or circadian rhythm dysfunction can make a person sleep for more than 18 hours a day– contrary to other sleep disorders where people find it difficult to fall asleep. This condition is more prevalent in teenage boys. 

The dysfunction in the thalamus, temporal lobe, and frontal lobe of the brain leads to a chronic degenerative condition known as Kleine-Levin Syndrome (KLS). Although, this is just speculation, and the exact cause is still not known. Similar to the above consideration, there are plenty of other causes of Kleine-Levin Syndrome (KLS) that we will discuss in the further sections below.

What is Sleeping Beauty Syndrome  

Kleine-Levin Syndrome, or as commonly referred to as Sleeping Beauty Syndrome, is a rare sleep disorder characterized by persistent episodic hypersomnia and mood changes. People with this neurological condition sleep their lives away. Roughly, one million people in the world suffer from Sleeping Beauty Syndrome. Out of the one million, 70 percent are males.

Imagine living under the fear of falling asleep at any moment without any warning or prior signals? People suffering from this condition have to give up everything from school, college education, a career, relationships, and much more. Apart from sleeping a lot, they also have to deal with other troublesome symptoms like temporary hearing loss and sudden increase in core body temperature.

Furthermore, this condition may or may not remain for the entire lifetime of the sufferer. In most cases, Kleine-Levin Syndrome lasts for a decade, with the patient experiencing recurrent episodes lasting more than a week or in rare cases a month. Ordinarily, a patient has one episode every six months. In between two episodes, the patient is perfectly healthy. The symptoms only begin to show after the relapse.

Symptoms of Kleine-Levin Syndrome (KLS)  

1) Hyperphagia (Excessive Hunger)

Hyperphagia (also known as Polyphagia) is a disorder involving an abnormal appetite for food. In half to two-thirds of cases, Kleine-Levin Syndrome patients suffer from excessive hunger during the entirety of the episodes. 

Excessive hunger after a long exercise session or a rough day at work is normal in healthy individuals. Also, after refueling, it subsides. But this is not the case in people suffering from Kleine-Levin Syndrome. They get hungrier as they eat, and sleep is the only way to make it go away. 

2) Hypersomnia 

We have already discussed the adverse effects of Kleine-Levin Syndrome on the sleep health of a patient. Hypersomnia (the antithesis of insomnia) is a neurological disorder involving excessive sleepiness. For someone suffering from hypersomnia, there is no such thing as a night of good sleep. They are sleepy regardless of it. 

Moreover, this condition should not be confused with chronic apathy or lethargy. A hypersomniac patient–unless they use a stimulant and a mood stabilizer like Modafinil– have no control over the situation. Research done by the University of Louisville School of Medicine, USA, proves the use of Modafinil as a stimulant– effective and safe for children.

3) Hypersexuality 

Hypersexuality is another symptom of Kleine-Levin Syndrome. During the relapsing-remitting episodes, the patient (in most cases, a male) experiences a sudden increase in libido or sexual desire. The behavior exerted by the patient is quite similar to the one someone with obsessive-compulsive disorder (OCD) might show.

Furthermore, hypersexuality has always been associated with dementia or other similar brain disorders. An injury or dysfunction in a particular part of the brain is considered to be the primary cause of hypersexuality.

As with Kleine-Levin Syndrome, vital parts of the brain like the thalamus, temporal lobe, and frontal lobe do not function the way they should. Hence, dysfunction in essential parts of the mind of a KLS patient leads to swings in sex drive, which in turn leads to socially inappropriate behaviors. 

Diagnosis of Kleine-Levin Syndrome (KLS)  

Diagnosis of Kleine-Levin Syndrome or the Sleeping Beauty Syndrome is entirely clinical. Meaning, there is no laboratory examination or medical imaging involved. The doctor has to identify the disease purely based on the signs, symptoms, and patient’s medical history. This is what makes it a challenge to diagnose this condition.

The exertion of symptoms like hyperphagia, hypersexuality, or hypersomnia can easily mislead a doctor to other commonly occurring conditions. However, with the technique of “exclusion,” it is possible to diagnose Kleine-Levin Syndrome in a patient. 

Here, by conducting a series of tests, the doctor rules out the possibility of other conditions that share symptoms. There cannot be any possibility of the patient having any other conditions like diabetes, hypothyroidism, obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), and many more. 

For instance, a person showing an increase in libido should not test positive for OCD, bipolar disorder, and Parkinson’s disease. Only then can the doctor provide treatment for Kleine-Levin Syndrome (KLS) or the Sleeping Beauty Syndrome.

Treatment Options of Kleine-Levin Syndrome (KLS)

1) Modafinil

Modafinil (sold under the brand name Provigil) is a stimulant used for the treatment of Kleine-Levin Syndrome (KLS). It improves wakefulness up to a certain degree. This is why it is used extensively for treating a litany of sleep ailments (leading to excessive daytime sleepiness) like shift-work sleep disorder, narcolepsy, and obstructive sleep apnea syndrome. 

Although Modafinil has been approved for medical use in the United States and the United Kingdom, it does come with some side effects. Some common ones include headache, anxiety, allergic reactions, and nausea. Also, to avoid the above-mentioned side effects, do not exceed the recommended dosage (200 mg orally once a day in the morning). 

2) Lithium

Although not safe for those with thyroid and kidney disorders, Lithium is proven to be effective in decreasing the length and frequency of relapsing-remitting episodes in patients with the Sleeping Beauty Disorder. According to a French study, there is no other drug that Lithium that demonstrates this level of evidence.

The researchers also studied the downsides of this drug. They turned out to be insignificant when compared to its benefits for a Kleine-Levin Syndrome patient. After treating 71 patients with Kleine-Levin Syndrome with 500–1600 mg of Lithium per day, they only found 35 five patients who exhibited symptoms like tremors, increased thirst, diarrhea, and subclinical hypothyroidism– only 5 had to stop treatment.

3) Carbamazepine (CBZ)

Carbamazepine (CBZ) (sold under the brand name Tegretol) works great for those who do not wish to risk the side-effects of Lithium. It is not as effective as Lithium but far better than other stimulants and energizers available in the market. Hence, used extensively by those suffering from Sleeping Beauty Syndrome.

Furthermore, even researchers agree with the claims of Carbamazepine being safer than Lithium. While treating a patient misdiagnosed with epilepsy, a medical professional at the American University of Beirut, Lebanon, discovered that carbamazepine could lessen the severity of its symptoms of Kleine-Levin Syndrome. The day this patient stopped taking carbamazepine, his symptoms returned. Hence, there is plenty of assurance for those who are skeptical about carbamazepine’s effectiveness.


Be it a teenager, adult, or elderly, Kleine-Levin Syndrome is one of the appalling sleep disorders out there. Things can get tricky during the “episodes” that last months at a time. During this period, patients sleep for 16-20 hours per day, waking up only to do the essential chores of daily living. 

Furthermore, a patient in his/her teens can manage to deal with the symptoms as they most likely will have a parent to support them. Imagine being a 30-something man/woman having to spend 2-3 months a year dormant.

But there is one unfortunate person in 1000 suffering from this condition. In the United States alone, there are 200,000 patients with Kleine-Levin Syndrome or Sleeping Beauty Syndrome.