Short answer: Armodafinil (Nuvigil) is a prescription wakefulness medicine for narcolepsy, sleepiness from obstructive sleep apnea, and shift work disorder. It is a Schedule IV controlled substance and the longer-lasting form of modafinil. It is milder than amphetamines but can cause serious rashes and makes hormonal birth control less effective.
Key takeaways
- What it is: Armodafinil is a wakefulness-promoting agent and a Schedule IV controlled substance in the US.
- Main uses: Narcolepsy; sleep apnea sleepiness; shift work disorder.
- Timing: effects start in 1 to 2 hours and last 10 to 15 hours.
- Most dangerous mix: Alcohol, which can cause masked tiredness; poor judgment.
- Naloxone: it does not reverse this drug, but give it whenever opioids could be involved.
- Dependence risk: Low.
- Legal route: only with a prescription from a DEA-registered clinician, filled by a licensed pharmacy.
What is armodafinil?
Armodafinil improves wakefulness in narcolepsy, in sleep apnea that remains sleepy despite CPAP, and in shift work disorder. It does not treat the cause of sleep apnea.
It is the longer-lasting half of modafinil, which explains its once-daily dosing and longer effect. It is used off-label for fatigue and studied for many conditions, but is not approved for boosting performance in healthy people.
Quick facts
| Fact | Armodafinil |
|---|---|
| Generic name | Armodafinil |
| Brand names | Nuvigil |
| Drug class | Wakefulness-promoting agent; R-enantiomer of modafinil |
| US legal status | Schedule IV, prescription only |
| Approved uses | Excessive sleepiness from narcolepsy, obstructive sleep apnea, or shift work disorder |
| Forms | Tablets (50, 150, 200, 250 mg) |
| Onset | 1 to 2 hours |
| Half-life | About 15 hours |
How long does armodafinil last?
- Starts working: 1 to 2 hours
- Effects last: 10 to 15 hours
- Half-life: About 15 hours
Timing varies with the dose, the form, how it is taken, liver and kidney function, age, and other drugs taken at the same time.
What are the biggest risks of armodafinil?
Common side effects include headache, nausea, dizziness, and trouble sleeping.
Serious rash: rare but life-threatening skin reactions, including Stevens-Johnson syndrome, and allergic swelling. Stop it at the first sign of a rash.
Birth control: it speeds the breakdown of hormonal contraceptives, which may fail during treatment and for a month after stopping.
What should you never mix with armodafinil?
| Combined with | What happens | Label guidance |
|---|---|---|
| Hormonal contraceptives (pills, patch, ring, implant) | Reduced effectiveness | Use another method during and for 1 month after |
| Cyclosporine | Lower cyclosporine levels | Monitor levels |
| Omeprazole, diazepam, phenytoin (CYP2C19 drugs) | Higher levels of these drugs | Monitor |
| Other stimulants or MAO inhibitors | Overstimulation, higher blood pressure | Use caution |
| Alcohol | Masked tiredness; poor judgment | Avoid |
Check any combination with the DoseUses combination checker or ask a pharmacist.
What are the signs of an armodafinil overdose, and what should you do?
Overdose causes insomnia, restlessness, agitation, anxiety, fast heartbeat, high blood pressure, and chest pain. Serious toxicity is uncommon compared with amphetamines.
If someone may be overdosing
- Call 911 for chest pain, a seizure, trouble breathing, signs of a stroke (face drooping, weakness on one side, slurred speech), a very high body temperature, or if the person collapses.
- Move them somewhere cool and calm, loosen tight clothing, and cool the skin with water. Do not try to hold them down.
- If they become unresponsive or their breathing slows, give naloxone. Street stimulants are often contaminated with fentanyl.
- For advice when the person is awake and stable, call Poison Help at 1-800-222-1222.
What is armodafinil withdrawal like, and how long does it last?
Stopping armodafinil after regular use does not cause dangerous physical withdrawal, but it can cause a temporary crash.
- Days 1 to 3CrashTiredness, increased sleep, hunger, and low mood.
- Week 1AdjustingLow energy, poor concentration, and irritability.
- Weeks 2 to 4SettlesMood and energy usually return to baseline.
See the withdrawal timelines and the full armodafinil withdrawal guide.
Is armodafinil legal?
In the United States, armodafinil is a Schedule IV controlled substance. The only legal way to get it is with a prescription from a clinician registered with the Drug Enforcement Administration (DEA), filled by a licensed pharmacy. Depending on state law, that can be a physician, nurse practitioner, or physician assistant.
- Refills: a Schedule IV prescription can be refilled up to five times within six months of the date it was written. After that, a new prescription is needed.
- Telehealth: federal flexibilities let DEA-registered clinicians prescribe Schedule II to V medicines after a telemedicine visit, without a prior in-person exam, through December 31, 2026. A permanent DEA rule was under final review in late 2026. State rules can be stricter.
- Monitoring: prescribers and pharmacists in most states check a prescription drug monitoring program, a database of controlled-substance prescriptions, before prescribing or dispensing.
Outside the United States
| Country | Status |
|---|---|
| United Kingdom | Not licensed (modafinil is a prescription-only medicine) |
| International | Not under UN control |
Frequently asked questions about armodafinil
What is the difference between Nuvigil and Provigil?
Nuvigil (armodafinil) is the longer-lasting R-form of modafinil (Provigil), so lower doses last longer.
Is armodafinil a stimulant?
It promotes wakefulness and is grouped with stimulants, but it works differently and has lower misuse potential than amphetamines.
Does armodafinil affect birth control?
Yes. Use a non-hormonal method during treatment and for a month after stopping.
Can armodafinil be used for ADHD?
It is not approved for ADHD.
Is Nuvigil a controlled substance?
Yes, it is Schedule IV.
Sources
- Nuvigil (armodafinil) prescription information, DailyMed, US National Library of Medicine.
- Controlled Substance Schedules, DEA Diversion Control Division.
- 21 CFR 1306.22, Refilling of prescriptions (Schedules III and IV), Electronic Code of Federal Regulations.
- Prescribing controlled substances via telehealth, US Department of Health and Human Services.
- BeSafeRx: Your Source for Online Pharmacy Information, US Food and Drug Administration.
- Safe Pharmacy, National Association of Boards of Pharmacy.
- One Pill Can Kill, US Drug Enforcement Administration.
- International drug control conventions, United Nations Office on Drugs and Crime.
This guide summarizes the sourced DoseUses Armodafinil profile, written from FDA labels, DEA rules, and federal health agencies. It is educational and is not medical advice. Last updated October 5, 2026.
