There are instances where both hypersomnia and insomnia have been observed in the same individual. Such instances of co-occurrence are generally observed along with psychiatric disorders, such a major depressive disorder.

Is hypersomnia the opposite of insomnia?

The more commonly known sleep disorder insomnia is a condition in which people can't sleep, whereas hypersomnia disorders involve excessive daytime sleepiness or the inability to stay awake during the day.

How many hours of sleep is hypersomnia?

Oversleeping is called hypersomnia or “long sleeping.” This condition affects about 2 percent of people. People with hypersomnia might require as many as 10 to 12 hours of sleep per night to feel their best.