Fladrafinil: Review of Nootropic Benefits, Uses, Dosage, & Side Effects

Updated on January 28, 2024
 by — reviewed by Jason Williams, PhD (Contributor: George Collins / Editor: Yoko Hill)
Review of Fladrafinil's nootropic benefits, uses, dosage, and side effects.

Fladrafinil has received a lot of attention in the nootropic community for its effect on brain function and ability to help people stay awake. Fladrafinil is often seen as an alternative to powerful nootropics such as modafinil and adrafinil.

Fladrafinil, also known as CRL-40,941 and fuorafinil, is a eugeroic drug related to adrafinil and modafinil (Provigil). It has dopaminergic, α-adrenergic and histaminergic activity.

But is Fladrafinil the right nootropic for you?

To decide, you first need to learn more about how Fladrafinil works in your nervous system, how to best dose it, the benefits it provides, and the potential side effects.

Rest assured that we will cover all of this information so that you can decide today if using Fladrafinil would be beneficial to your wellness routine. Read on!

What is Fladrafinil?

Fladrafinil (also known as CRL-40,941, bis(4-fluorophenyl)-Adrafinil​ or fluorafinil) is a eugeroic smart drug that’s 3-4 times more potent than adrafinil, with the same effects as modafinil, along with a similar chemical structure.(1)

However, what distinguishes Fladrafinil from modafinil and adrafinil is that it has an additional fluorine atom attached to one of the benzene rings. This fluorine substitution is thought to contribute to its increased potency and pharmacokinetic profile. 

Fladrafinil is considered a prodrug of modafinil, meaning that it is metabolized and transformed into modafinil in the body. Fladrafinil also has a longer half-life than most other stimulant drugs, including modafinil. This property makes it a better choice for those needing a more prolonged boost of their ability to concentrate throughout the day or night.

Although the optimal dosage varies, Fladrafinil requires a lower dosage than both modafinil and adrafinil to achieve the same results.

Fladrafinil is a popular nootropic that was originally developed in the 1970s by the French pharmaceutical company Lafon Laboratories as an experimental treatment for narcolepsy.

Fladrafinil works by increasing the levels of dopamine, norepinephrine, and histamine in the brain. As a result, Fladrafinil improves working memory, concentration, attention span, motivation, mood, and overall cognitive function.

In addition, taking Fladrafinil helps people perform at their best, enabling them to beat daytime sleepiness or fatigue during long hours at work. This is due to the stimulant effects of fladrafinil, which make it similar to adrafinil and modafinil.

However, Fladrafinil may be the better choice for many who are looking for a more potent nootropic that provides the same effects as modafinil and adrafinil.

Fladrafinil is widely acknowledged in the nootropic community for its ability to improve cognitive function and increase wakefulness without the jitters typically associated with stimulants, such as caffeine pills or capsules.


  • Increased wakefulness and ability to concentrate
  • Ability to reduce anxiety and promote a better mood
  • Enhanced memory, learning, and executive cognitive function
  • Longer half-life compared to other stimulants


  • Limited scientific evidence from human studies regarding its safety, efficacy, and long-term use
  • Risk of dependence and withdrawal symptoms

Mechanism of Action

Fladrafinil (acetamide, 2-[[bis(4-fluorophenyl)methyl]sulfinyl]-N-hydroxy), is often available as Fladrafinil powder.

Once taken in (through pill, capsule, liquid solution or powder form) the body will metabolize fladrafinil to produce the powerful nootropic known as modafinil. Although the effects of modafinil are similar to those of fladrafinil, modafinil has a shorter half-life.

The mechanism of action of the nootropic compound known as fladrafinil is diverse. While not fully understood, it’s important to understand its key aspects.

One of the primary mechanisms of action of fladrafinil is its ability to stimulate the brain’s neurotransmitter systems.

Fladrafinil acts as a dopamine reuptake inhibitor and increases the stimulation of dopamine transporters, making more of this neurotransmitter available in the brain.

André Nieoullon has found that higher levels of dopamine in the brain allow for increased motivation, concentration, and pleasure.(2) However, dopamine is not only important for mood and reward but also plays a role in memory formation and consolidation.

Additionally, having higher norepinephrine levels promotes increased alertness and arousal. It is also associated with the formation of memories, particularly in response to novel or emotionally charged events.(3)

Fladrafinil also enhances the activity of glutamate, the primary excitatory neurotransmitter involved in learning and memory, helping to improve cognitive ability and performance.(4) Conversely, Fladrafinil reduces the production of gamma-aminobutyric acid (GABA), a neurotransmitter responsible for promoting relaxation and sleep, hence its wakefulness-promoting properties.

Evidence from multiple researchers also suggests that fladrafinil may influence histamine levels in the brain, contributing to its effects on alertness and wakefulness.(5) This is particularly useful for those with sleep disorders, such as narcolepsy and sleep apnea. An increase in histamine can also lead to greater attentiveness and engagement with tasks, potentially leading to better memory encoding and recall.

CRL-40,941’s efficacy as a cognitive enhancer makes it a popular choice among professionals and students alike. Fladrafinil is suitable for anyone aiming to boost their cognitive performance, focus, and motivation.

Nootropic Benefits of Fladrafinil

Fladrafinil has become one of the top OTC choices in the fast-growing market for cognitive enhancement supplements. 

Fladrafinil is a prodrug that converts into the active agent known as modafinil in the body. Although fladrafinil offers a wider range of cognitive benefits without the limitations of its alternative.

Known for improving focus, productivity, motivation, and alertness, discover the benefits of Fladrafinil and how it can be a game-changer for optimizing brain performance.

1. Increases Alertness and Wakefulness

Fladrafinil is known for its wakefulness-promoting properties. It is a popular choice for individuals looking to combat daytime sleepiness, especially those dealing with narcolepsy or sleep apnea.

The substance acts as a eugeroic agent, helping people stay awake and alert without the jitters often associated with caffeine.

Fladrafinil can help people fight fatigue and improve alertness, making it an effective agent for those needing to remain vigilant during demanding tasks or work.

2. Enhances Cognitive Function

Fladrafinil has been shown to enhance the activity of neurotransmitters like dopamine and norepinephrine in the brain, which are involved in learning and memory.

This potent cognitive enhancer can help improve cognitive ability and performance, potentially making it a better choice for those needing boosting focus, such as individuals with ADHD.

3. Improves Memory Retention

By increasing the concentration of dopamine, norepinephrine, and histamine, fladrafinil enhances enhance cognitive processes, including memory.

As a eugeroic, fladrafinil promotes wakefulness, which can also indirectly support memory by reducing fatigue and improving focus.

4. Improves Mood

Due to its influence on dopamine levels, taking fladrafinil may provide mood-enhancing effects. By increasing levels of dopamine, the neurotransmitter associated with pleasure and reward, fladrafinil can improve overall mood and well-being.

5. Potential Therapeutic Effects

While not officially approved for medical use, fladrafinil, a derivative of adrafinil, may have therapeutic benefits in managing disorders related to a lack of alertness or cognitive deficits. As with modafinil and adrafinil, fladrafinil has the potential to be used in a therapeutic setting under medical supervision.

Uses of Fladrafinil

Fladrafinil, a potent eugeroic nootropic, is gaining attention for its ability to boost alertness, wakefulness, and cognitive performance. 

Below are the primary uses of fladrafinil:

  • Study and Work Aid: Due to its ability to help people stay awake and alert, fladrafinil is a sought-after substance for students and professionals engaging in prolonged periods of work or study.
  • Management of Daytime Sleepiness: For those struggling with daytime sleepiness, fladrafinil can provide a much-needed boost to help them stay functional and productive.
  • Nootropic Stacking: Some nootropic enthusiasts may include fladrafinil powder in their nootropic stacks to enhance the effects of other cognitive enhancers. This minimizes the need for high dosages.

Where To Buy Fladrafinil

For those wondering where to buy fladrafinil online, it’s crucial to choose high-quality fladrafinil products from top-notch vendors, ensuring you’re receiving pure material that’s effective and third-party tested.

Our pick for the best vendor to buy CRL-40,941 powder is Science.Bio. This website provides the best quality nootropics and chemical products. It has also proven to be a trustworthy online vendor.

All the Science.Bio products, including fladrafinil, have been third-party tested, and their products are shipped worldwide. 

Fladrafinil Dosage

Determining the optimal dosage for fladrafinil varies widely depending on individual sensitivity, tolerance, body chemistry, and the specific reasons for use.

A common starting point for new users is often on the very low end, sometimes as low as 30 to 80 milligrams per day.

More experienced users may take higher doses, but it is generally advised not to exceed 200 mg per day to minimize the risk of experiencing severe negative side effects of fladrafinil.

It is critically important for anyone considering taking fladrafinil to:

  1. Start with a low dose: To assess tolerance, begin with the lowest possible dose and only increase it gradually if necessary.
  2. Be cautious of frequency: Avoid daily use to prevent tolerance and potential dependence.
  3. Monitor for side effects: If any new or concerning side effects occur, then you should prompt discontinue the use of fladrafinil and consult with a healthcare provider.

Fladrafinil Side Effects & Safety

When using any research chemical, including the use Fladrafinil, it’s essential to be aware of the potential negative side effects. 

Fladrafinil side effects may include:

  • Insomnia (or low sleep quality)
  • Anxiety
  • Potential impacts on liver function (due to the metabolism process)

Some users may find that combining fladrafinil with other nootropics like L-theanine supplements or Choline supplements, can minimize potential negative side effects while enhancing cognitive benefits.


By boosting dopamine, histamine, and norepinephrine, the eugeroic effects of fladrafinil provide several cognitive benefits. Fladrafinil’s able to boost your ability to concentrate, reduce fatigue, and improve memory and learning abilities. All of these properties have made Fladrafinil a popular choice in the nootropic community.

However, it’s important to purchase high-quality fladrafinil powder from top-notch vendors and consult with health professionals regarding its use and dosage.

With proper care and informed decisions, individuals can harness the potential benefits of fladrafinil while minimizing potential adverse effects, ensuring a safe and effective cognitive boost!


How long does Fladrafinil take to work?

Fladrafinil typically begins to work within 1 to 3 hours after ingestion. However, the onset time can vary depending on individual factors like metabolism and stomach content.

What is the elimination half-life of Fladrafinil?

The elimination half-life of fladrafinil is approximately 15 hours. This means that it takes around 15 hours for 50% of the substance to be cleared from your system.

Should you cycle Fladrafinil?

Yes, it’s recommended to cycle fladrafinil to prevent tolerance buildup and potential side effects. A common cycle might involve taking fladrafinil for 5 days and then taking 2 days off.

Can I stack Fladrafinil with other compounds?

Stacking fladrafinil with other compounds can potentially increase its effectiveness. However, it’s important to research each compound thoroughly and consult with a healthcare professional before starting any new stack.

Sources, Studies, and Scientific Research
  1. Dowling, Geraldine et al. “Outsmarted by nootropics? An investigation into the thermal degradation of modafinil, modafinic acid, adrafinil, CRL-40,940 and CRL-40,941 in the GC injector: formation of 1,1,2,2-tetraphenylethane and its tetra fluoro analog.” Drug testing and analysis vol. 9,3 (2017): 518-528. doi:10.1002/dta.2142 ↩
  2. Nieoullon, André. “Dopamine and the regulation of cognition and attention.” Progress in neurobiology vol. 67,1 (2002): 53-83. doi:10.1016/s0301-0082(02)00011-4 ↩
  3. Prokopová, I. “Noradrenalin a chování” [Noradrenaline and behavior]. Ceskoslovenska fysiologie vol. 59,2 (2010): 51-8. ↩
  4. McEntee, W J, and T H Crook. “Glutamate: its role in learning, memory, and the aging brain.” Psychopharmacology vol. 111,4 (1993): 391-401. doi:10.1007/BF02253527 ↩
  5. Gerrard, Paul, and Robert Malcolm. “Mechanisms of modafinil: A review of current research.” Neuropsychiatric disease and treatment vol. 3,3 (2007): 349-64. ↩