Awakening to the psychopharmacology of sleep and arousal: novel neurotransmitters and wake-promoting drugs.

Exciting new developments in the psychopharmacology of wakefulness are clarifying the neurotransmitters, pathways, and drugs that impact this important physiologic state. Selectively inducing normal wakefulness without stimulating external vigilance may lead to therapeutic benefits not only in sleep disorders but also in cognitive disorders and conditions associated with fatigue.