Modafinil
Wellness
In plain English
Modafinil is an FDA-approved medicine that promotes wakefulness. It is used to treat excessive sleepiness from narcolepsy, shift-work sleep disorder, and obstructive sleep apnea (alongside CPAP). It is taken by mouth and is often preferred over older stimulants because it is less jittery and has lower abuse potential, though it is still a controlled substance. Headache is the most common side effect; rare serious skin reactions and interactions with hormonal birth control are important cautions.
The science
Modafinil promotes wakefulness primarily by inhibiting dopamine reuptake (raising extracellular dopamine) and modulating orexin, histamine, and other arousal systems, with a pharmacology distinct from classical amphetamines. In a randomized, double-blind, placebo-controlled trial in narcolepsy, modafinil significantly reduced pathological daytime somnolence and improved wakefulness measures (US Modafinil in Narcolepsy Multicenter Study Group, 1998). It is FDA-approved for narcolepsy, shift-work disorder, and residual sleepiness in treated obstructive sleep apnea; off-label "cognitive enhancement" use is common but not an approved indication. Headache, nausea, and anxiety are common; rare serious rash (including Stevens-Johnson syndrome) and reduced efficacy of hormonal contraceptives are notable; it is a Schedule IV controlled substance.