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armodafinil

Adjunctive therapy

Brand: Nuvigil

Published 2025-12-23 · Last reviewed 2025-12-30 · 4 references

Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.

Print sheet Review evidence

At a glance

Class: Adjunctive therapy·Typical dose: Narcolepsy or OSA: 150–250 mg once daily in the morning (label).·Half-life: Steady-state mean 15 h·LAI available: No

Class: Adjunctive therapy
Typical dose: Narcolepsy or OSA: 150–250 mg once daily in the morning (label).
Half-life: Steady-state mean 15 h
LAI available: No

Quick answers

What is armodafinil?: Armodafinil (brand Nuvigil) is a wakefulness-promoting medication indicated to improve wakefulness in adults with excessive sleepiness associated with narcolepsy, obstructive sleep apnea (OSA), or shift work disorder (SWD) (label).
What is Nuvigil?: Nuvigil is a brand name for armodafinil.
What is Nuvigil (armodafinil) used for?: Label indications include: Improve wakefulness in adults with excessive sleepiness associated with narcolepsy, obstructive sleep apnea, or shift work disorder (label).
What drug class is Nuvigil (armodafinil)?: Wakefulness Agent.
What is the mechanism of action of Nuvigil (armodafinil)?: Wakefulness-promoting agent (R-enantiomer of modafinil) indicated for excessive sleepiness in narcolepsy, obstructive sleep apnea (as adjunct to primary therapy), and shift work disorder; Schedule IV with clinically important rash/hypersensitivity warnings and CYP-mediated interaction potential.
What strengths does Nuvigil (armodafinil) come in?: Tablets: 50 mg, 150 mg, 200 mg, and 250 mg (label).

General information

Armodafinil (Nuvigil) is a wakefulness-promoting medication indicated to improve wakefulness in adults with excessive sleepiness associated with narcolepsy, obstructive sleep apnea (OSA), or shift work disorder (SWD) (label).

It is the longer-acting R-enantiomer of modafinil and is a Schedule IV controlled substance. It is sometimes discussed off-label for fatigue or residual sleepiness in psychiatric settings, but use is individualized and requires monitoring for activation and insomnia (label/clinical).

Serious rash and hypersensitivity reactions are rare but safety-critical; discontinuation is recommended at the first sign of rash unless clearly not drug-related (label).

Psychiatric adverse reactions (anxiety, agitation, mania, psychosis, suicidal ideation) have been reported; monitoring is especially important in bipolar-spectrum illness, psychosis, or high baseline anxiety (label/clinical).

The armodafinil compare view, evidence feed, and print page support review of activation, insomnia, and interaction profiles.

U.S. approvals

Excessive sleepiness associated with narcolepsy, OSA, or shift work disorder (adults) (2007)

Formulations & strengths

Tablets: 50 mg, 150 mg, 200 mg, and 250 mg (label).

Generic availability

Available generically.

Armodafinil is widely used for excessive sleepiness and may be preferred when longer duration is desired, but careful patient selection is important due to psychiatric activation risk, serious rash warnings, and CYP-mediated drug–drug interaction potential (label/clinical).

View labelExact

Mechanism of action

Refer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.

The precise mechanism is not fully established. Clinical descriptions emphasize wake-promoting effects and effects on monoaminergic signaling, including dopaminergic pathways (label/clinical).

Armodafinil is the R-enantiomer of modafinil; compared with racemic modafinil, systemic exposure of the R-enantiomer is higher at steady state, contributing to a longer duration profile (label).

Wakefulness promotion (mechanism not fully established; label).

Metabolism & pharmacokinetics

Apparent terminal elimination half-life is ~15 hours; steady state is reached within about 7 days with once-daily dosing (label).
Armodafinil induces CYP3A4/5 and can inhibit CYP2C19, which may reduce exposure to CYP3A substrates and increase exposure to CYP2C19 substrates; interaction review is clinically important (label).

Dosing & administration

Narcolepsy or OSA: 150–250 mg once daily in the morning (label).
Shift work disorder: 150 mg once daily approximately 1 hour prior to the start of the work shift (label).
For OSA, armodafinil is not a substitute for primary therapies; it is used as adjunctive therapy when residual sleepiness persists alongside an OSA management plan (label/clinical).
In clinical practice, late-day dosing is avoided due to insomnia risk; dose timing is a frequent early follow-up topic (clinical).

Monitoring & labs

Rash and hypersensitivity monitoring, especially early in treatment (label).
Blood pressure and heart rate monitoring, especially with cardiac risk factors (label/clinical).
Mood and psychiatric symptom monitoring (anxiety, agitation, mania/psychosis) (label/clinical).
Sleep disruption monitoring (insomnia, timing effects) (clinical).
Drug interaction review (CYP3A induction; CYP2C19 inhibition), including contraception counseling (label).

Adverse effects

FDA boxed warnings

Common side effects (≥10%)

Headache: Common and often dose-related (label/clinical).
Nausea: Often improves over time; assess hydration and food intake (clinical).
Insomnia: Longer duration increases sensitivity to late-day dosing; morning dosing helps (label/clinical).
Anxiety / agitation: Can occur; monitor closely in anxiety and bipolar-spectrum illness (label/clinical).
Dizziness: Can affect driving and fall risk early in treatment (clinical).

Other notable effects

Serious rash (including Stevens-Johnson syndrome) and hypersensitivity reactions have been reported; discontinue at first rash unless clearly not drug-related (label).
Psychiatric symptoms (mania, psychosis, suicidal ideation, aggression) have been reported; risk appears higher with prior psychiatric history (label/clinical).
Cardiovascular effects (blood pressure/heart rate increases) can occur; monitoring is commonly considered in patients with risk factors, especially when combined with other stimulants (label/clinical).

Interactions

CYP3A4 induction can reduce exposure to steroidal contraceptives and other CYP3A substrates; counseling about reduced hormonal contraceptive effectiveness is an important practical step (label).
CYP2C19 inhibition can increase exposure to CYP2C19 substrates (diazepam, propranolol, omeprazole, some tricyclic antidepressants); interaction review is important in polypharmacy (label/clinical).
Combined use with other activating agents can increase anxiety, insomnia, and cardiovascular effects; monitoring is commonly considered (clinical).

Other useful information

AASM evidence reviews and guidelines support wake-promoting agents for excessive daytime sleepiness in central hypersomnolence disorders, but medication choice is individualized based on comorbidities, interaction burden, and adverse-effect profiles (AASM/clinical).
In psychiatric augmentation discussions (fatigue/residual sleepiness), clinicians often document symptom targets and a time-bounded reassessment plan to reduce long-term polypharmacy without clear benefit (clinical).

References

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