Insomnia is characterized by difficulty falling asleep and maintaining sleep. Insomnia may be transient, meaning it lasts a few days, or chronic, which can last for weeks or months. This condition is often caused by daily stress, depression, panic, poor sleep hygiene, caffeine, alcohol, chronic pain, asthma, shift work or jet lag.
Narcolepsy is a sleep disorder in which you experience sleepiness attacks, dreaming while awake. You may fall asleep suddenly, even while eating, walking or driving. Narcolepsy can also cause hallucinations.
OBSTRUCTIVE SLEEP APNEA (OSA)
Obstructive sleep apnea (OSA) means that breathing stops during sleep due to the collapse of the upper airway. This repeated airway collapse leads to apneas, arousals and low blood oxygen levels. OSA can cause excessive daytime sleepiness and is associated with increased risk of cardiovascular diseases and driving accidents.
RESTLESS LEG SYNDROME
Restless leg syndrome is characterized by a strong urge to move your legs associated with crawling sensations in the legs. These uncontrolled movements can cause frequent arousals and disruption in your sleep.
SHIFT WORK DISORDER
About 10 percent of people who work outside the traditional 9 a.m. to 5 p.m. workday experience difficulty sleeping when sleep is desired, needed or expected. Symptoms include excessive sleepiness when you need to be awake and insomnia when you need to sleep.