Modafinil Half-Life | How Long Does the ‘High’ Last?

Tomas Thorne

Last Updated: February 20, 2023

Modafinil Half-Life

Curious about the Modafinil half-life and how long the nootropic lasts?

Research and users’ experiences tell us that there’s no point in taking Modafinil to skyrocket your focus and increase your productivity — unless you know what benefits to expect and WHEN to expect them.

The Modafinil half-life lasts for quite a while, which can help with pulling an all-nighter. But taken at the wrong time, Modafinil is known to prevent the user from getting a good night’s sleep.

We’ll detail how to avoid that and more below.

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Disclaimer: The contents of are for informational and educational purposes only. We do not provide legal advice. Likewise, we do not provide medical advice, diagnosis, or treatment. Please consult your physician prior to consuming Modafinil or related nootropics. Your access to is subject to our full Disclaimer and Terms of Use.

What is Modafinil?

Before we can talk about the half-life of Modafinil, let’s discuss how this smart drug works and why it has achieved popularity worldwide across a variety of competitive industries.

Modafinil is a wakefulness-promoting drug that is commonly used by narcolepsy patients to treat excessive daytime sleepiness and help them function properly during normal work hours [1].

While it is FDA-approved for other medical conditions such as shift work sleep disorder and obstructive sleep apnea, researchers are currently testing Modafinil for other purposes [1]:

“Modafinil has also been tried on disease-related fatigue, attention-deficit disorder, Alzheimer’s disease, age-related memory decline, depression, idiopathic hypersomnia, cognitive impairment in schizophrenia, myotonic dystrophy, post-anaesthesia grogginess, everyday cat-napping, and jet-lag treatment”

Since Modafinil can demonstrably reduce fatigue and enhance alertness in military soldiers, many people have started using Modafinil as a lifestyle drug for off-label purposes. Some of these include:

  • Increased focus
  • Long-lasting alertness for 10-12 hours
  • Enhanced memory
  • Improved mood

While its mechanism of action is still not definitive to this day, scientists have uncovered some fundamental properties of Modafinil that explain why it works the way it does [2]:

“[Modafinil] also acts at a hypothalamic level, most likely stimulating the tuberomammillary nucleus and hypocretin (orexin)-producing neurons, and it reduces GABA release in cortex and posterior hypothalamus.

It, therefore, may activate wakefulness-promoting cerebral regions and inhibit sleep-promoting nuclei”

It’s no wonder why students, CEOs, pilots, entrepreneurs, and surgeons have started using Modafinil to power through complex and difficult tasks.

Modafinil helps you sustain your attention for long periods of time that may otherwise not be possible in normal circumstances (such as pulling an all-nighter).

Modafinil and Half-Life | The Basics

We know how Modafinil works, but that’s not enough to transition into a discussion about Modafinil half-life.

First, we need to gain a brief yet thorough understanding of what the term “half-life” means.

When nootropic users talk about the half-life of Modafinil they are referring to its “biological half-life” [3]:

“…the period of time required to reduce the amount of a drug in an organ or the body to exactly one half its original value due solely to biological elimination”

Alternatively, medical researchers will refer to this term as the “elimination half-life” [4]:

“…Time it takes for the plasma concentration or the amount of drug in the body to be reduced by 50%.”

So after one half-life, the drug’s concentration in the body will be half of the dose consumed (50%). Once another half-life passes by, the drug’s concentration will be 25% of the original dose, and so on.

Just to make sure you understand the math, News Medical provides a great explanation of how a drug’s elimination half-life works over a longer period of time [5]:

“With each additional half-life, proportionally less of the drug is eliminated. However, the time required for the drug to reach half of the original concentration remains constant.

In general, the effect of the drug is considered to have a negligible therapeutic effect after 4 half-lives, that is, when only 6.25% of the original dose remains in the body.”

So whenever the half-life of Modafinil is discussed from this point on, you can assume we are talking about Modafinil’s biological half-life (a.k.a. elimination half-life).


What is the Half-Life of Modafinil?

So, what is the Modafinil half-life number we need to know about? And with that information, how long does Modafinil last with respect to its cognition-enhancing effects?

Different studies have come up with several ranges to account for the fact that Modafinil can have a longer or shorter therapeutic duration depending on the individual user:

  • The official product monograph says “The effective elimination half-life of modafinil after multiple doses is about 15 hours” [6].
  • One study published on therapeutic advances in narcolepsy said the Modafinil half-life was 9-14 hours [7], while a systematic review of Modafinil’s multiple uses claimed it was 12-15 hours [8].
  • An earlier study evaluating Modafinil’s tolerability in healthy male volunteers reported a flat Modafinil half-life of 15 hours [9].

Rather than pore through hundreds of scientific studies yourself, we’ll give you a “rule of thumb” benchmark to follow…

For a standard Modafinil dose of 100-200 mg, the half-life can be anywhere from 12-15 hours.

Which leads us to ask about Modafinil’s effects and how long they last.

How Long Does Modafinil Last?

Please keep in mind that even though Modafinil might stay in your system for a few days, its effects don’t last for the same period of time.

If you look at a graph of Modafinil’s blood concentration in the body over time, you will notice that it generally peaks at around hours 1-2 [10].

This lines up with an official medical recommendation for shift workers to take Modafinil roughly 1 hour before their shift begins [11].

However, many of our research participants have reported that they started feeling Modafinil “kick in” as early as 30 minutes after taking the smart drug.

They also reported that the “Modafinil high” (i.e. enhanced focus and alertness) lasts anywhere between 10-12 hours before it tapers off.

Combining the half-life of Modafinil with this information, we can come up with our own rules of thumb when timing your Modafinil dose…

  • We take our Modafinil before 10am if we want to fall asleep by 11pm-2am
  • We take our Modafinil dose as early in the morning as possible
  • WE DO NOT take Modafinil after 1pm unless we’re looking to pull an all-nighter.


Knowing that the half-life of Modafinil lasts 12-15 hours, we can deduce some benefits of taking Modafinil that are supported by scientific studies and anecdotal testimonials from nootropic users.

The half-life of Modafinil ensures a few things. Here are some of the positives:

Long-Lasting Focus

One of the greatest aspects of the Modafinil experience is how long one can stay focused. It’s almost as if boring and complicated tasks suddenly become fun and enjoyable to engage with.

This was confirmed in a systematic review examining the use of cognition-enhancing drugs in unfocused youth who were not diagnosed with ADHD [12]:

“Participants believed that improvements would be greater than they were, which the authors contributed to increased vigor.

In non-sleep-deprived participants, modafinil does not appear to induce over-confidence in cognitive abilities (although the authors found a trend towards overconfidence in post-task self-monitoring measures), while still improving cognitive performance in logical reasoning (accuracy and response times), vigilance and serial reaction time”

Some people end up switching to Modafinil entirely because it “heightens alertness as much as caffeine does” [13].

Productive, Energetic All-Nighters

For those needing to past midnight all the way until the sun rises, Modafinil may help maintain a high level of alertness and bypass the need to sleep [14]:

“Results indicate that modafinil is efficacious for sustaining/restoring objective performance and alertness during sleep deprivation with few adverse effects. At appropriate dosages, modafinil restores performance and alertness to non-sleep deprived levels”

Even government officials will anonymously admit to using Modafinil for meeting extremely tight deadlines [15]:

“Senior public servants relied on drugs to keep them awake during 20-hour shifts in the race to put together Budget papers.”

“ has been told by a user that modafinil was needed to endure a string of long shifts broken by as little as a four- or five-hour break.”

“For years, federal and state budgets and other economic statements have required public servants in Finance and Treasury to dump their already extended working hours and stay at their desks longer”

Lack of Jitters, Anxiety or Withdrawal Symptoms

Have you ever felt “overwhelmed” or jittery after taking other stimulants? If so, Modafinil may be a good alternative worth looking at [16]:

“Unlike the amphetamines, for example, modafinil is reported to have minimal peripheral side effects at therapeutic doses. It also appears to have a low abuse potential, does not interfere with normal sleep, and does not seem to produce tolerance”

Many users have reported feeling much less anxious and aggressive when taking Modafinil compared to other stimulants, which allows for one’s focus to be “smoother” and more uninterrupted [17].

generic version of Armodafinil


The half-life of Modafinil can also work against those who do not know how to use the drug properly. Here are a few downsides of Modafinil’s half-life:

Lack of Sleep / Interference with Sleep Cycle

Make no mistake about it: Modafinil can — and will — interfere with the user’s regular sleep cycle.

For example, if you normally get to sleep before midnight but end up falling asleep at 3 AM after using this smart drug, you may experience a hangover effect after Modafinil. This would usually be due to the change in one’s sleep cycle [18].

Considering how Modafinil’s effects can last up to 12 hours, the Modafinil “high” can go on for much longer than a user might like it to.

Additionally, Modafinil is NOT a replacement for sleep. Continuously using it to avoid sleeping 7-8 hours a night over an extended period of time could be dangerous to mental health [18]:

“If somebody takes modafinil long-term, they may develop some of the same deficits in slow-wave sleep as cocaine users…Slow-wave sleep is the deep sleep that we tend to get early in the night.

But by taking a stimulant that forces the body to be awake more than it wants to be, you’re disrupting its ability to regulate how much sleep it gets and the kind of sleep it gets, so it never feels properly refreshed.”

Even as much as a single week of sleep deprivation can significantly diminish your body’s immune system and cognitive functioning.

You MUST Be Productive

This anecdotal downside of Modafinil’s half-life has been frequently mentioned to us, and we ourselves have experienced it, so it is worth mentioning here.

Before taking a dose of Modafinil, it is imperative to have a game plan for the things to get done that day.

Once you swallow the Modafinil pill, you should start working immediately and sustain your focus on the task at hand. When Modafinil’s effects kick in, we find that we’re able to operate on “autopilot” with respect to focusing on any given task.

However, this has also worked against us.

For example, one of our research leads was watching YouTube videos when his Modafinil kicked in. What do you think happened? Yep, he spent the next several hours watching YouTube, unable to consciously force himself to stop and get back to his work.

In other words: We see no point in taking Modafinil unless one fully intends to invest their energy into the tasks that require the cognitive boost Modafinil provides.

Armodafinil vs. Modafinil | Half-Life Differences

What are the half-life differences between Modafinil and Armodafinil, a drug consisting of the most potent enantiomer (i.e non-superimposable mirror image) of Modafinil?

Surprisingly, both Armodafinil and Modafinil have very similar half-lives.

According to one pharmacokinetic study, the half-life of Modafinil is 14.4 hours while the Armodafinil half-life is 16.5 hours [19].

This makes sense as Armodafinil is the “R” enantiomer of Modafinil, which has a half-life of ~15 hours while the “S” enantiomer has a half-life of just 4 hours.

However, one pivotal study points out that the duration of effects is notably different in both drugs [20]:

“Despite similar half-lives, plasma concentrations following armodafinil administration are higher late in the day than those following modafinil administration on a milligram-to-milligram basis. The different pharmacokinetic profile of armodafinil may result in improved wakefulness throughout the day in patients with ES compared with modafinil”

In short, the Armodafinil half-life and Modafinil half-life are similar in their length of time, but Armodafinil leads to greater wakefulness sustained over the working day.

Finding the Ideal Modafinil Dosage

Knowing the Modafinil half-life and how long it lasts, here are the guiding questions we, individually ask ourselves to determine an “ideal” Modafinil dosage and when to take it [19]:

  • How long do I want to stay focused?
  • When do I want to go to sleep tonight?
  • Am I experiencing any unwanted side effects with this dose?

Even then, we keep in mind that everyone is biochemically unique and may react to Modafinil differently.

After all, 100mg of Modafinil may “work” for 12 hours in one individual and only 6-8 hours in another individual.

Therefore, we can conclude that most individuals would be well-advised to start at a Modafinil dose of 100mg taken early in the morning 1-3 times a week.

Speaking from experience, our team members have generally started this way and have gradually increased their dose in 25mg or 50mg increments, experimenting with the new dose for an additional week.

None of us go above 200mg of Modafinil daily as the effects do not appear to significantly improve beyond that amount.

We’ll leave you with some additional tips from research participants who have successfully used the half-life of Modafinil to their own advantage. These tips may or may not enhance your Modafinil experience and lead to the “Modafinil high” you’re looking for:

  • Take 100mg Modafinil at 7-8 am and another 100mg at 12-1 pm to maintain maximum blood concentrations of Modafinil throughout the day
  • Taking Modafinil on an empty stomach may lead to different results, versus taking it with food


Half-Life of Modafinil | The Verdict

So, what is the magical “Modafinil half-life” number smart drug users need to know about?

To sum it up: If you are taking a standard Modafinil dose of 100-200mg, it has a half-life of 12-15 hours in your system.

The effects are long-lasting, so don’t expect to sleep for at least 12 hours. For most users, this means taking Modafinil before lunch or even the early morning.

This does not apply for those using Modafinil to pull all-nighters.

Others enjoy using the smart drug to pull all-nighters.

No matter your goals, use the information above to ensure you’re using Modafinil in the most beneficial way possible. As always, please consult with your prescribing doctor before acting on this information.

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  1. Kim D. Practical use and risk of modafinil, a novel waking drug. Environ Health Toxicol. 2012;27:e2012007. doi:10.5620/eht.2012.27.e2012007
  2. Caraceni A, Simonetti F. Psychostimulants: new concepts for palliative care from the modafinil experience?. J Pain Symptom Manage. 2004;28(2):97‐99. doi:10.1016/j.jpainsymman.2004.04.006
  3. Half Lives. Retrieved June 5, 2020.
  4. HALF-LIFE. Retrieved June 6, 2020.
  5. What is the Half-Life of a Drug? Retrieved June 4, 2020.
  6. PROVIGIL® (modafinil) Tablets [C-IV]. Retrieved June 4, 2020.
  7. Thorpy M. Therapeutic advances in narcolepsy. Sleep Med. 2007;8(4):427‐440. doi:10.1016/j.sleep.2007.03.004
  8. Kim D. Practical use and risk of modafinil, a novel waking drug. Environ Health Toxicol. 2012;27:e2012007. doi:10.5620/eht.2012.27.e2012007
  9. Wong YN, Simcoe D, Hartman LN, et al. A double-blind, placebo-controlled, ascending-dose evaluation of the pharmacokinetics and tolerability of modafinil tablets in healthy male volunteers. J Clin Pharmacol. 1999;39(1):30‐40. doi:10.1177/00912709922007534
  10. Wong YN, King SP, Laughton WB, McCormick GC, Grebow PE. Single-dose pharmacokinetics of modafinil and methylphenidate given alone or in combination in healthy male volunteers. J Clin Pharmacol. 1998;38(3):276‐282. doi:10.1002/j.1552-4604.1998.tb04425.x
  11. Modafinil. Retrieved June 3, 2020.
  12. Bagot KS, Kaminer Y. Efficacy of stimulants for cognitive enhancement in non-attention deficit hyperactivity disorder youth: a systematic review. Addiction. 2014;109(4):547‐557. doi:10.1111/add.12460
  13. A Safe Drug to Boost Brainpower. Retrieved June 2, 2020.
  14. Wesensten NJ. Effects of modafinil on cognitive performance and alertness during sleep deprivation. Curr Pharm Des. 2006;12(20):2457‐2471. doi:10.2174/138161206777698819
  15. Public servants used drug, modafinil, to stay awake to complete the Federal Budget on time. Retrieved June 5, 2020.
  16. Lyons TJ, French J. Modafinil: the unique properties of a new stimulant. Aviat Space Environ Med. 1991;62(5):432‐435.
  17. Modafinil & Anxiety Reduction. Retrieved June 3, 2020. r/modafinil
  18. Is modafinil safe in the long term? Retrieved June 2, 2020.
  19. Darwish M, Kirby M, D’Andrea DM, Yang R, Hellriegel ET, Robertson P Jr. Pharmacokinetics of armodafinil and modafinil after single and multiple doses in patients with excessive sleepiness associated with treated obstructive sleep apnea: a randomized, open-label, crossover study. Clin Ther. 2010;32(12):2074‐2087. doi:10.1016/j.clinthera.2010.11.009
  20. Darwish M, Kirby M, Hellriegel ET, Robertson P Jr. Armodafinil and modafinil have substantially different pharmacokinetic profiles despite having the same terminal half-lives: analysis of data from three randomized, single-dose, pharmacokinetic studies. Clin Drug Investig. 2009;29(9):613‐623. doi:10.2165/11315280-000000000-00000

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