Idiopathic hypersomnia


Idiopathic hypersomnia is a rare sleep disorder characterized by excessive daytime sleepiness, even following a sufficient night’s sleep, and difficulty waking up after sleep. The exact cause of this condition is unknown. Individuals with idiopathic hypersomnia often experience a lack of refreshment after naps, accompanied by confusion and disorientation upon waking. 

This disorder can manifest at any time, posing potential dangers, especially when engaged in activities like driving or working. The onset of idiopathic hypersomnia is typically gradual, and its diagnosis involves excluding more common sleep disorders. Treatment aims to manage symptoms through the use of medications.  


The primary symptom is experiencing excessive daytime sleepiness. Additionally, individuals may: 

  • Develop headaches. 
  • Encounter difficulty waking up in the morning or after naps. 
  • Sleep for 911 hours or more within a 24hour period. 
  • Struggle with performing routine daily activities. 
  • Not feel refreshed after sleep or naps. 
  • Experience cognitive fog. 


The exact cause of idiopathic hypersomnia (IH) remains unknown, but there are several possible explanations. Some people with IH have a family history of the condition or other sleep disorders like narcolepsy. Neurotransmitters like dopamine and serotonin, which regulate mood and happiness, may also play a role. Additionally, low levels of histamine, a brain chemical involved in immune function and allergy symptoms, could contribute to IH. Other potential causes include infections, brain damage, and anxiety or depression. 

IH might also be triggered by certain factors such as an irregular sleep schedule, certain medications, and other underlying sleep conditions.