Abstract
* Tasimelteon (Hetlioz) is the first drug approved for the treatment of non-24-hour sleep-wake (non-24) disorder in patients with total blindness. Non-24 disorder occurs when a person's 24-hour circadian rhythm isn't regulated in the brain because it can't receive the daylight that normally acts as a stimulus. Those afflicted will have a circadian rhythm longer than 24 hours, leading to a periodic extended inability to sleep at night.
* The most common adverse effects of tasimelteon are headache, elevated liver enzyme levels, nightmares or unusual dreams, disturbed sleep, upper respiratory or urinary tract infection, and drowsiness.