Hypersomnolence is a sleep disorder characterised by excessive sleepiness.
Other symptoms may include difficulty coming to complete wakefulness, confusion, disorientation, poor motor co-ordination and physical and cognitive slowness. These symptoms may affect a person’s ability to function well in family, social and occupational settings.
Hypersomnolence may be idiopathic (unknown cause), or it may be as a result of a co-existing medical condition, drug abuse or medication.
Hypersomnolence can be associated with certain syndromes, such as Prader-Willi syndrome, Norrie disease or Niemann-Pick disease, as well as neurodegenerative disorders such as Alzheimer’s disease or Parkinson’s disease. It may also occur in conjunction with other health conditions, such as depression, celiac disease, head trauma, fibromyalgia, or following an acute viral infection.