What are the causes of recurrent hypersomnia and the detection methods for causes pls?thanks

See sleep specialist: Hypersomnia can be caused by other sleep problems, such as sleep apnea or narcolepsy. It can also caused by dysfunction of the autonomic nervous system as well as drug or alcohol abuse, brain injuries, head trauma, brain tumors, or physical problems can also cause hypersomnia. Obesity, epilepsy, encephalitis, or multiple sclerosis can cause hypersomnia as well. Please see a sleep doctor for workup.