Short answer: Modafinil (Provigil) is a wakefulness-promoting medicine for excessive sleepiness from narcolepsy, obstructive sleep apnea, and shift work disorder. It is milder than amphetamines and a Schedule IV controlled substance. It can make hormonal birth control less effective.
Key takeaways
- What it is: Modafinil is a wakefulness-promoting agent and a Schedule IV controlled substance in the US.
- Main uses: Narcolepsy; sleep apnea; shift work disorder.
- Timing: effects start in about 1 hour and last 10 to 12 hours.
- Most dangerous mix: Alcohol, which can cause not well studied.
- 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 modafinil?
Modafinil is approved to improve wakefulness in adults with excessive sleepiness from narcolepsy, obstructive sleep apnea (alongside CPAP, not instead of it), and shift work disorder.
It is thought to work mainly by blocking dopamine reuptake, more weakly than stimulants, and by affecting other wake-promoting systems such as orexin and histamine.
Quick facts
| Fact | Modafinil |
|---|---|
| Generic name | Modafinil |
| Brand names | Provigil; related armodafinil (Nuvigil) |
| Drug class | Wakefulness-promoting agent |
| US legal status | Schedule IV, prescription only |
| Approved uses | Excessive sleepiness from narcolepsy, obstructive sleep apnea, shift work disorder |
| Forms | Tablets |
| Onset | About 1 hour; peak 2 to 4 hours |
| Half-life | About 15 hours |
| Broken down by | Liver (CYP3A4); induces CYP3A4 |
How long does modafinil last?
- Starts working: About 1 hour
- Effects last: 10 to 12 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 modafinil?
Common side effects include headache, nausea, nervousness, runny nose, back pain, diarrhea, anxiety, and insomnia.
Serious risks include rare but life-threatening skin reactions (Stevens-Johnson syndrome), allergic reactions, psychiatric symptoms such as mania or psychosis, and chest pain or palpitations in people with heart disease.
Warning: Modafinil can make hormonal birth control, including pills, patches, rings, and implants, less effective during treatment and for one month after stopping. Use another method too.
What should you never mix with modafinil?
| Combined with | What happens | Label guidance |
|---|---|---|
| Hormonal birth control | Lower hormone levels; contraceptive failure | Use backup contraception |
| Cyclosporine, some HIV drugs | Lower levels | Monitor |
| Omeprazole, diazepam, phenytoin (CYP2C19 substrates) | Higher levels | Monitor |
| MAOIs | Possible interaction | Use caution |
| Alcohol | Not well studied | Avoid |
Check any combination with the DoseUses combination checker or ask a pharmacist.
What are the signs of a modafinil overdose, and what should you do?
Overdose causes insomnia, restlessness, agitation, confusion, anxiety, fast heartbeat, high blood pressure, and chest pain. Deaths from modafinil alone are rare.
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 happens when you stop modafinil?
Stopping modafinil does not usually cause withdrawal. Sleepiness returns. A few people feel tired or low for several days.
- Day 1Sleepiness returnsThe underlying condition reappears.
- Days 2 to 7Possible fatigueMild tiredness or low mood in some people.
- OngoingTreat the causeCPAP, scheduled naps, and other treatments.
See the withdrawal timelines and the full modafinil withdrawal guide.
Is modafinil legal?
In the United States, modafinil 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 | Prescription-only medicine; not a controlled drug |
| Canada | Prescription medicine |
| Australia | Schedule 4 prescription medicine |
| International | Not under UN control |
Frequently asked questions about modafinil
Is modafinil a stimulant?
It promotes wakefulness and has mild stimulant-like effects, but it is weaker than amphetamines and has a lower risk of misuse.
Is modafinil a "smart drug"?
Studies in healthy, rested people show small effects on some tasks at best. Buying it without a prescription online is illegal and products may be counterfeit.
Does modafinil affect birth control?
Yes. It can make hormonal birth control fail during use and for a month after stopping.
What is armodafinil?
Armodafinil (Nuvigil) is the longer-lasting active half of modafinil, given at lower doses.
Sources
- Provigil (modafinil) prescribing 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 Modafinil profile, written from FDA labels, DEA rules, and federal health agencies. It is educational and is not medical advice. Last updated October 5, 2026.
