Modafinil (Provigil): Half-Life, Label and Uses | Dose Track
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Modafinil: half-life, strengths and approval status

Tablet strengths · Approval status · Half-life ~15 hours

Short answer: Modafinil has a half-life of about 15 hours. Levels peak 2 to 4 hours after a dose. People vary, so treat these as estimates.

What is modafinil?

Modafinil is a wakefulness-promoting drug sold as Provigil and as generic tablets. The FDA label approves it to improve wakefulness in adults with excessive sleepiness from narcolepsy, obstructive sleep apnea or shift work disorder. It is a Schedule IV controlled substance.

Also known as: Provigil.

Tablet strengths

Provigil comes as 100 mg and 200 mg tablets.

Approval status and how it is used

The FDA Provigil label dose is 200 mg once a day in the morning for narcolepsy or sleep apnea, or 200 mg about 1 hour before the work shift for shift work disorder. Doses up to 400 mg a day were well tolerated, but the label says there is no consistent evidence of more benefit than 200 mg. In sleep apnea it treats the sleepiness, not the blocked airway. It is not approved for children. Use for focus or study in healthy people is off-label; a 2015 systematic review of studies in healthy, rested people (Battleday) found that most showed better executive function, about half showed better attention or memory, and studies using more complex tests found more consistent gains.

The label warns about serious rashes, including Stevens-Johnson syndrome, and says to stop at the first sign of a rash unless it is clearly unrelated. It also warns about psychiatric symptoms, and it can make hormonal birth control less effective during use and for one month after stopping. Modafinil is Schedule IV because it can be misused or lead to dependence. See also armodafinil.

Modafinil half-life and time to peak

  • Half-lifeabout 15 hours
  • Time to peak (Tmax)2 to 4 hours

The FDA Provigil label gives an effective elimination half-life of about 15 hours after repeated doses, with peak levels 2 to 4 hours after a dose and steady state after 2 to 4 days. Modafinil is a 50:50 mix of R- and S-modafinil, and the R form lasts about three times longer. Food does not change total absorption but can delay the peak by about an hour.

Numbers shown are taken from the source above. Half-life varies from person to person.

How to track modafinil in Dose Track

  1. Add modafinil as a custom compound. Start typing its name and Dose Track fills in the details from its research library for you to check, and it sits next to everything else you take.
  2. Log each tablet when you take it, including split or fractional tablets, so your history shows exactly what you took and when.
  3. Set reminders on your own schedule, whether that is daily, weekly or every few days.
  4. Your log is stored on your phone and no account is needed. Data only leaves it for features you choose, like AI answers and lab reading.

How Dose Track handles peptides · Reconstitution calculator · Half-life calculator

ArmodafinilNuvigil · half-life about 15 hours

Frequently asked questions

What is the half-life of modafinil?+
The FDA Provigil label gives an effective elimination half-life of about 15 hours after repeated doses, with peak levels 2 to 4 hours after a dose and steady state after 2 to 4 days. Modafinil is a 50:50 mix of R- and S-modafinil, and the R form lasts about three times longer. Food does not change total absorption but can delay the peak by about an hour.
Is modafinil a controlled substance?+
Yes. The FDA Provigil label lists it as Schedule IV (C-IV), because it can be misused or lead to dependence.
Does modafinil affect birth control?+
Yes. The FDA label says it can make steroidal birth control (such as ethinyl estradiol) less effective while taking it and for one month after stopping, and recommends another or an added method.
Can I track modafinil in Dose Track?+
Yes. Modafinil is in Dose Track's research library, so when you add it as a custom compound its details are filled in for you to check. You can then log each tablet next to your other compounds, set reminders on your own schedule, and see your history next to your lab results. Your log is stored on your phone and no account is needed. Data only leaves it for features you choose, like AI answers and lab reading.

Sources

  1. Provigil (modafinil) prescribing information, sections 1, 2, 3, 5, 7, 9 and 12.3. DailyMed, March 2025.
  2. Battleday RM, Brem AK. Modafinil for cognitive neuroenhancement in healthy non-sleep-deprived subjects: a systematic review. Eur Neuropsychopharmacol. 2015;25(11):1865-1881.

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