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Modafinil is a prescription medicine for narcoleptics that increases alertness and prevents sleep. It just so happens to also increase cognition and memory, and is a potent and highly regarded supplement in the category of nootropics.

Our evidence-based analysis on modafinil features 61 unique references to scientific papers.

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Summary of Modafinil

Primary information, health benefits, side effects, usage, and other important details

Modafinil is an awakefulness enchancing drug that was created for treatment of daytime sleep related disorders such as Narcolepsy. It seems to have benefits for cognition via increasing levels of stimulatory neurotransmitters in the brain, and is used recreationally as a smart-drug.

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How to Take

Recommended dosage, active amounts, other details

Standard dosages are 100-200mg, or perhaps 4mg/kg bodyweight, either taken in a sleep deprived state (if the user desires to not fall asleep) or taken first thing in the morning if the user does not wish to impair sleep.

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Human Effect Matrix

Unlocked for Examine members

The Human Effect Matrix summarizes human studies to tell you what effects Modafinil has on your body, how much evidence there is, and how strong these effects are.

Full details are available to Examine members.
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
grade-b Notable Very High See all 6 studies
Fatigue is notably reduced with modafinil supplementation, particularly during instances of sleep deprivation or hypersomnia.
grade-b Minor Low See all 3 studies
There may be a slight increase in systolic blood pressure with acute usage of modafinil (when measured at its peak blood levels), although it does not appear to modify basal blood pressure values
grade-b Minor High See all 4 studies
Cognition is significantly improved in persons undergoing sleep deprivation or other conditions in which attention processing is highly impaired, while other conditions (cognitive decline or drug dependence) experience minor improvements in cognition that are lesser than those seen in sleep deprivation.
grade-b Minor High See all 3 studies
An improvement in reaction time (decrease) is noted in both healthy and normal persons as well as those undergoing either drug addiction or sleep deprivation. This may be related to the alertness promoting effects of the compound.
grade-b Minor Very High See all 5 studies
An improvement in working memory is noted in most persons tested, even otherwise healthy and nonfatigued controls.
grade-b - Very High See all 3 studies
Heart rate and pulse do not appear to be influenced from modafinil supplementation, despite a small increase in systolic blood pressure.
grade-c Strong Very High See 2 studies
Modafinil (300mg) taken prior to sleep is as potent as 20mg D-amphetamine in reducing the need to sleep and improving cognitive performance during intentional sleep deprivation. Occasionally, this potency manifests itself as the 'side-effect' of insomnia in some persons who take it in the AM
grade-c Notable - See study
Modafinil appears to be able to reduce symptoms of ADHD in children when taken as a daily preventative at the lowest active dose
grade-c Notable Very High See 2 studies
Subjective well being and enjoyment during cognitive tasks appears to be significantly improved modafinil supplementation, and this is notable as it has been noted to occur in otherwise healthy persons taking modafinil for nootropic purposes
grade-c Minor - See study
Alcohol dependence, particularly the impulsivity thereof, appears to be slightly reduced with modafinil administration
grade-c Minor - See study
An increase in alertness has been reported in persons using modafinil supplementation.
grade-c Minor - See study
Modafinil appears to be able to reduce appetite, and 'loss of appetite' is a common side-effect of modafinil supplementation.
grade-c Minor Moderate See 2 studies
There appears to be somewhat of an increase in subjective attention with modafinil secondary to its arousal promoting effects
grade-c Minor Very High See 2 studies
Modafinil can decrease impulsivity in studies assessing addiction, although it appears to only significantly affect those with higher baseline impulsivity (more impulsive at the start of the study) rather than all persons.
grade-c Minor Very High See 2 studies
Memory (usually studies investigate short term) appears to be beneficially influenced with modafinil supplementation, possible secondary to the improvements in working memory and attention.
grade-c Minor - See study
Motivation to complete a cognitive task appears to be improved in persons supplementing modafinil.
grade-c Minor - See study
There is a possible improvement in processing accuracy with supplementation of modafinil.
grade-c Minor Very High See 2 studies
Memory impairment in multiple sclerosis may be attenuated with supplementation of modafinil (250mg armodafinil), although other cognitive impairments associated with MS do not appear significantly affected.
grade-c - - See study
There do not appear to be any significant influences on self-reported ratings of calmness with supplementation of modafinil.
grade-c - - See study
There does not appear to be a significant influence on processing speed, with some evidence suggesting a possible reduction thereof.
grade-c - - See study
There is currently no evidence to suggest a significant reduction of weight associated with modafinil, although as a trend to reduce weight has been noted alongside appetite reduction it is thought that modafinil could have a role in weight control.

Studies Excluded from Consideration

  • Is an extension of a trial already included in the above table[1]

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Things to Note

Is a Form Of

Other Functions:

Also Known As

2-[(Diphenylmethyl) sulfinyl]acetamide, Provigil, Modalert, Modapro, Alertex

Do Not Confuse With


  • At least in the US and Canada, Modafinil is labeled a prescription drug and may not be easily acquirable. It is a Schedule IV controlled substance in the US.

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Click here to see all 61 references.