REM sleep behavior disorder
RBDREM sleep behavior disorder is a parasomnia in which the normal muscle paralysis of REM sleep is lost, so people physically act out their dreams.
Episodes can involve talking, shouting, punching, kicking or leaping from bed, often in response to dreams of being chased or attacked, and can injure the sleeper or a bed partner. It most often affects men over fifty and is strongly associated with Parkinson's disease, Lewy body dementia and multiple system atrophy, frequently appearing years before those diagnoses. It can also be triggered by certain antidepressants or by withdrawal from alcohol.
Diagnosis requires overnight polysomnography showing muscle activity during REM sleep together with a history of dream enactment. Because of its link to neurodegenerative disease, neurologists usually follow affected people over time. Cannabidiol has been examined in a small number of preliminary studies in this disorder, and the evidence is too limited to draw conclusions.