What Are Rare Sleep Disorders?

Last Updated: JAN 19, 2024

Sleep disorders are a common issue that can affect people of all ages and can have significant impacts on physical and mental health. While disorders like insomnia and sleep apnea are well known and widely discussed, there are also several rare sleep disorders that are not as well known or understood. In this post, we will explore some of the rarest sleep disorders and their causes, symptoms, and treatments. Understanding these conditions can help people recognise if they or a loved one may be experiencing a rare sleep disorder and seek proper medical evaluation and treatment.

Rare sleep disorders

What are the rarest sleep disorders?

Kleine-Levin Syndrome

This is a rare disorder characterised by recurrent episodes of excessive sleepiness, altered behavior, and abnormal eating and sexual behaviors. These episodes can last for days or weeks and are often accompanied by fever and irritability. The cause of Kleine-Levin Syndrome is not known, but it is thought to be related to changes in the brain's hypothalamus and may be triggered by infections, head injuries, or other physiological changes.

Rapid Eye Movement Sleep Behavior Disorder (RBD)

This disorder is characterised by abnormal behavior during the rapid eye movement (REM) stage of sleep, including acting out vivid dreams or nightmares. People with RBD may physically act out their dreams, which can lead to injury or harm to themselves or their bed partners. RBD is often associated with Parkinson's disease and other neurological conditions.

REM Sleep Without Atonia

This disorder is characterised by the inability to fully relax the muscles during REM sleep, which can lead to the person physically acting out their dreams. This can lead to injury or harm to themselves or their bed partners.

Nocturnal Sleep-Related Eating Disorder (NS-RED)

This disorder is characterised by the uncontrolled consumption of food during sleep. People with NS-RED often have no memory of eating during the night and may consume unusual or unhealthy food items. This disorder is often associated with obesity, sleep apnea, and other sleep disorders.


This is a neurological disorder that affects the brain's ability to regulate sleep-wake cycles. People with narcolepsy experience excessive daytime sleepiness and may have sudden, irresistible sleep attacks. They may also experience hallucinations and sleep paralysis. Narcolepsy is caused by a deficiency of the neurotransmitter hypocretin, which regulates sleep and wakefulness.

It's important to note that these sleep disorders are rare and may require specialised evaluation and treatment. If you suspect that you or a loved one may be experiencing a sleep disorder, it is important to speak with a healthcare professional for proper diagnosis and treatment.