What Are Some Causes of Severe Sleepiness?

Insufficient sleep, staying up late at night, alcohol or drug use, smoking, and inadequate physical activity can cause severe sleepiness, reports WebMD. Obesity, medications and depression may also lead to excessive sleepiness. Some people feel extremely sleepy due to restless legs syndrome or sleep apnea.

People with restless legs syndrome experience an uncomfortable feeling in the legs, causing an intense impulse to move the limbs, explains WebMD. They find it difficult to sleep properly, because jerky leg motions often worsen while sleeping or resting. Lack of sleep leads to sleepiness during the day. Doctors may recommend taking folate, vitamin B12 or iron supplements to lessen restless legs syndrome. Avoiding nicotine, alcohol and caffeine, eating healthy foods, exercising frequently, and practicing relaxation techniques also mitigate symptoms.

Sleep apnea results from the collapse of the upper airway for 10 or more seconds while sleeping, states WebMD. The upper airway tends to collapse hundreds of times throughout the night. An airway obstruction causes obstructive sleep apnea, while central sleep apnea occurs due to the failure of the brain to deliver signals to the muscles responsible for breathing. People with sleep apnea usually snore and gasp for air as their breathing becomes disrupted, leading to improper sleep and excessive sleepiness in the morning.