When a person that is suffering from hypersomnia always seems to be oversleeping. Many teenagers and younger adults have hypersomnia. A hypersomnia person tends to sleep numerous hours during the day and also during the night. During the oddest moments a person is likely to fall asleep. 

This dangerous sleeping disorder, hypersomnia, is also associated with another disorder known as narcolepsy. A hypersomniac and narcoleptic has been known to fall asleep while they are cooking or even driving. 

The cause of this disorder varies from each individual. However, sleep apnea is a medical disorder that is acquainted with hypersomnia. Injuries to the nervous system, traumas, or even tumors are some problems that could cause a person to have this medical condition. Also if a person is having withdraws from a drug or is on a certain medication, then hypersomnia could be the case. Several medical conditions can lead to hypersomnia such as: epilepsy, depression, obesity, encephalitis, and also multiple sclerosis. In some cases, hereditary or genes have been the cause factors.