What is it?
What modafinil is
2Modafinil is a wakefulness-promoting prescription drug. The U.S. DailyMed label for Provigil lists adult excessive sleepiness associated with narcolepsy, obstructive sleep apnea and shift work disorder as indications; it does not address the underlying airway obstruction in OSA.
Strongest evidence is clinical wakefulness support
2The label-backed evidence concerns wakefulness in specific excessive-sleepiness disorders. In OSA, the label emphasizes that modafinil addresses excessive sleepiness and is not a substitute for care directed at the underlying airway obstruction.
Healthy cognition evidence is real but narrower
3A systematic review of healthy non-sleep-deprived subjects found that modafinil showed more consistent benefits on complex attention, executive-function and learning tasks than on simpler tests. A 200 mg healthy-volunteer study found improvements on difficult planning, working-memory and decision-making tasks, but not every learning or creativity endpoint improved.
Names, aliases and forms
Potential effects and evidence map
Modafinil has strong clinical evidence for labeled wakefulness indications and a separate off-label cognition literature. DailyMed labeling recommends 200 mg once daily in the morning for narcolepsy or OSA-related excessive sleepiness, and 200 mg about one hour before a shift for shift work disorder. In healthy non-sleep-deprived subjects, a 2015 systematic review found more consistent benefits on complex attention, executive function and learning tasks than on simpler tests, while a 2013 placebo-controlled study using 200 mg reported benefits on demanding planning, working-memory and decision-making tasks. These findings must be balanced against prescription-only, Schedule IV and serious safety issues.
Modafinil has strong clinical evidence and U.S. label indications for improving wakefulness in specific excessive-sleepiness disorders.
Healthy-volunteer evidence supports benefit on some complex attention and executive-function tasks, but this remains off-label and task-dependent.
Learning and working-memory findings are mixed but positive in some complex-task settings.
Task enjoyment and persistence may increase in some studies, but motivation is not a labeled indication and can come with insomnia or misuse risk.
Typical dosages and timing
The U.S. label recommends 200 mg once daily in the morning for narcolepsy or OSA-related excessive sleepiness, and 200 mg about one hour before a shift for shift work disorder. Lower dosing may be considered in severe hepatic impairment or older patients under clinical care. This is label context, not self-directed dosing advice.
Timing & effect horizon
Safety, side effects and risk profile
In the U.S. label, modafinil is a Schedule IV controlled substance; its prescription-only use is jurisdiction-specific.
Common adverse reactions include nervousness, anxiety, insomnia, dizziness and headache; timing errors can disrupt sleep and safety-sensitive tasks.
The label advises increased monitoring in known cardiovascular disease and includes blood-pressure/cardiac cautions.
The label states that based on animal data, modafinil may cause fetal harm; pregnancy or conception planning requires specialist review.
The label includes clinically relevant drug interaction concerns, including hormonal contraceptive effectiveness and CYP-related changes.
Headache, nausea, dizziness, diarrhea and nervousness are among common adverse reactions in labeling.
Practical buying and quality notes
- Verify prescription legitimacy, jurisdiction, manufacturer, tablet strength, pharmacy status and whether the product matches a regulated label. Avoid loose tablets, imported blister packs with unclear provenance, and vendors that present controlled-drug access as ordinary supplement shopping.2
FAQ
Is modafinil a normal nootropic supplement?
2No. It is a prescription wakefulness-promoting drug and a Schedule IV controlled substance in the U.S. label, not an ordinary dietary supplement.
Does modafinil improve healthy cognition?
3Some healthy-subject studies show benefits on demanding attention, executive-function and working-memory tasks. The evidence is task-dependent and does not remove prescription, safety or legal constraints.
What dose is on the U.S. label?
2The label commonly uses 200 mg once daily in the morning for narcolepsy or OSA-related excessive sleepiness, and 200 mg about one hour before shift work. Individual dosing belongs in clinical care.
References
- PubChem. Compound Summary for CID 4236, Modafinil.
- DailyMed. PROVIGIL (modafinil) tablet prescribing information. Label published December 10, 2025; revised February 2025.
- Battleday RM, Brem AK. Modafinil for cognitive neuroenhancement in healthy non-sleep-deprived subjects: a systematic review. European Neuropsychopharmacology. 2015.
- Muller U, Rowe JB, Rittman T, Lewis C, Robbins TW, Sahakian BJ. Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers. Neuropharmacology. 2013.