The causes of narcolepsy are varied, with the following common causes
Sleep deprivation due to work or other external factors; abuse of substances such as alcohol and cannabis; sleep aids and opioids, benzodiazepine use, and physical illnesses such as neurological and medical disorders.
There are also rare sleep disorder-like disorders that can trigger narcolepsy, such as episodic sleeping sickness, idiopathic hypersomnia, Kleine-Levin syndrome (recurrent hypersomnia, periodic hypersomnia), sleep-related breathing disorders (e.g., obstructive sleep apnea), and circadian rhythm sleep-wake disorders.