Adrafinil vs Modafinil: Difference explained in plain English!

Adrafinil vs Modafinil: Difference explained in plain English!

Adrafinil vs Modafinil  What is the difference?

Adrafinil and Modafinil are nootropic substances which are very closely related, both having near identical effects (Wakefulness and Alertness) Modafinil acts faster however is harder to obtain as is controlled in most countries around the world.


Adrafinil vs Modafinil 7 main differences

  1. Pharmacology
    Adrafinil is a precursor that is converted to Modafinil in the body; therefore the effects of the two drugs are nearly identical
  2. Legal Status
    Adrafinil is marketed online and sold as a nootropic and nutraceutical, whereas Modafinil can only be purchased online illegally
  3. Schedule
    Adrafinil is unregulated in the US and may be sold as a dietary supplement; Modafinil is a schedule IV drug (US), requiring a prescription
  4. Potency
    Adrafinil is less potent than Modafinil; therefore, higher doses are usually required to achieve the same effect
  5. Dosage.
    A typical dose of Adrafinil is 300-600mg vs 200mg for Modafinil
  6. Half-life.
    The half-life of Adrafinil is about ~5 hours, but the effects last much longer because Modafinil is the active metabolite and has a 14-hour half-life
  7. Characteristics.
    Adrafinil is a whitish powder with an orange tint, whereas Modafinil is white or off-white



Adrafinil Molecular structure
Modafinil Molecular Structure

Adrafinil and Modafinil overview

Many stimulant chemicals, such as caffeine, methylphenidate (Ritalin®), Adderall® (amphetamine salts) dexedrine, and methamphetamine, are known to produce similar alerting/energising effects, yet are highly addictive.


Modafinil (Provigil) and Adrafinil have been described as gentler stimulants with much less anxiety, agitation, jitteriness, excess locomotor activity and insomnia associated with conventional stimulants.

Central nervous stimulants (CNS) such as Amphetamine or Pemoline are the most widely used drugs to treat narcolepsy, Hypersomnia and Catoplexy, but these have a number of well documented problems, such as cardiovascular side effects, interference with sleep, psychiatric disturbances and addiction. The use of these “classic” stimulants such as amphetamines threaten to reduce total sleep time and REM sleep, this will ultimately mean higher and higher doses are required and thus creates cycle of dependency.

How it works

Adrafinil is metabolized into Modafinil in the body. Functionally speaking Adrafinil and Modafinil have identical pharmacological effects. These effects include, increased arousal and vigilance, decreased fatigue and possibly enhanced cognitive function in some subjects.

But since Modafinil is the active metabolite of Adrafinil, and not all Adrafinil is converted to Modafinil in the body (some is converted to the inactive metabolite, Modafinilic acid), Adrafinil is less potent than Modafinil.


Adrafinil & Modafinil sleep patterns

In contrast to stimulants like amphetamine and caffeine, Modafinil (Provigil) and Adrafinil do not disturb sleep patterns or cause withdrawal symptoms. The effects of Modafinil (Provigil) and Adrafinil are totally different from the other psychostimulants such as amphetamine, caffeine, or ephedrine. These substances only lead to fleeting stimulation and cause problems of tolerance when they are used for long periods.


Adrafinil & Modafinil anxiety?

Modafinil (Provigil) and Adrafinil nootropics do not stimulate dopaminergic neurons in the nigrostriatal region of the brain [De Sereville et al. ,1994]. As a result, the stimulatory effect of Modafinil (Provigil) and Adrafinil on vigilance and locomotor activity (movement) is not associated with anxiety side effects [Simon et al,1994).

Furthermore, in a double-blind cross-over study of 16 “healthy volunteers” (half men and half women, all moderate caffeine users), Warot and colleagues [1993] found that the subjective effects of Modafinil (Provigil) “differed markedly” from amphetamine and were “close” to those of an equal amount of caffeine. They concluded that modafinil “does not possess amphetamine-like subjective effects in a healthy population,” and speculated that it probably has low abuse potential.



Adrafinil vs Modafinil Wakefullness

Wakefulness and Alertness

The effects of Modafinil (Provigil) and Adrafinil are based on their ability to selectively stimulate adrenergic neuron receptors in the brain (hypothalamus and brain stem) thought to be involved in regulating normal wakefulness and general alertness towards the external environment.


These sites are receptive to Norepinephrine (Noradrenaline), a neurotransmitter linked to alertness, learning, and memory. They work by directly stimulating the neurological postsynaptic receptor sites called, alpha-1 adrenergic.


The central function of Norepinephrine is a fairly recent discovery, it appears to regulate alertness and the waking-sleep cycle and has a role in the maintenance of attention, memory, learning, cerebral plasticity and even has neuro-protection qualities.


Stimulation without raising heart rate

As Adrafinil and Modafinil  nootropics work directly on sites that control alertness and doesn’t interfere with any other brain function, it has been proven a very successful treatment. It should be noted that this direct action means that mental stimulation is achieved without affecting heart rate or raising blood pressure.


The more focused activity profile may account for the relative lack of adverse side effects of  Modafinil (Provigil) and Adrafinil.  In addition, using Modafinil (Provigil) and Adrafinil does not require “catching up sleep” or “rebound sleep”. Theoretically, it is possible to stay awake on Modafinil (Provigil) and Adrafinil for hundreds of hours without sleeping.

This is in contrast to more conventional stimulants, which stimulate a broader range of brain receptors, including those involving dopamine.


Adrafinil vs Modafinil tablets


Key points of Adrafinil – Modafinil 

  • Promotes daytime wakefulness without affecting ability to sleep when sleep is desired
  • Works selectively through the brain’ s sleep-wake centers to activate only the cortex, not the entire brain
  • Efficacy established objectively and subjectively in numerous clinical trials
  • Among the safest stimulants available
  • Promotes wakefulness without generalised CNS stimulation in preclinical models
  • Has none of the side effects associated with stimulants such as amphetamine, caffeine, ephedrine, etc
  • Can safely be used without danger of addiction
  • Does not affect normal sleep patterns
  • Acts selectively through the sleep/wake centers of the brain believed to regulate normal wakefulness
  • Does not mediate wakefulness by a dopaminergic mechanism
  • Increases alertness without elevating motor activity
  • Improves patients ability to stay awake and participate in daily activities
  • Does not interfere with nighttime sleep architecture or with patients ability to fall asleep when needed
  • Improves attention and concentration
  • Enhances clarity of thought, cognitive function, mental focus, and memory
  • Normalizes sleep patterns
  • Reduces mental fatigue
  • Improves wakefulness in patients with excessive daytime sleepiness (EDS) associated with narcolepsy


 What is Adrafinil Modafinil –  used for

  • General physical and mental fatigue including shift work sleep disorder
  • Improve wakefulness in patients with excessive sleepiness
  • Narcolepsy (excessive daytime sleepiness) – FDA Approved
  • Hypersomnia (excessive sleep)
  • Catoplexy (a condition of sudden muscular weakness or fatigue)
  • Alzheimer’s disease
  • Senility and age-related memory decline
  • Depression
  • Myotonic dystrophy
  • Attention-deficit disorder (ADD)
  • Athletics and athletic training regimes
  • US Army, USAF, Special Forces, (as recently as Afghanistan and Iraq) French Foreign Legion, Dutch and Belgian military



Adrafinil used to be prescribed for Narcolepsy (Narcolepsy is a condition that causes excessive daytime sleepiness and a tendency to fall asleep suddenly in inappropriate situations. Sleep Attacks), the standard dose would be 600mg, twice a day. More recently, Modafinil is used for this purpose, the dosage being 100 – 200mg taken first thing in the morning.


Adrafinil vs Modafinil Infographic

Adrafinil vs Modafinil Infographic


Side Effects

Both Nootropics are considered safe, below are a list of possible side effects:

Common (may affect up to 1 in 10 people):

  • Dizziness.
  • Difficulty sleeping (insomnia).
  • Awareness of your heart beat, which may be faster than normal.
  • Chest pain
  • Flushing.
  • Dry mouth.
  • Loss of appetite, feeling sick, stomach pain, indigestion, diarrhoea or constipation.
  • Weakness.
  • Numbness or tingling of the hands or feet (‘pins and needles’).
  • Blurred vision.
  • Abnormal blood test results showing how your liver is working (increased liver enzymes).
  • Irritability


Uncommon (1 in 100 people):

  • Back pain, neck pain, muscle pain, muscle weakness, leg cramps, joint pain, twitching or tremor.
  • Vertigo (spinning sensation).
  • Difficulty moving muscles smoothly or other movement problems, muscle tension, coordination problems.
  • Hay-fever symptoms, runny nose/watery eyes.
  • Increased cough, asthma or shortness of breath.
  • Skin rash, acne or itchy skin.
  • Sweating.
  • Changes in blood pressure (high or low)
  • Abnormal heart trace.
  • Difficulty swallowing, swollen tongue or mouth ulcers.
  • Increased appetite,
  • Being sick (vomiting)
  • Weight Changes
  • Migraine.
  • Speech problems.
  • Diabetes with increased blood sugar.
  • High blood cholesterol.
  • Swollen hands and feet.
  • Abnormal urine or more frequent urination.
  • Disrupted sleep or abnormal dreams,
  • Loss of sex drive.
  • Nosebleeds
  • Abnormal vision or dry eyes.
  • Abnormal periods.
  • Abnormal blood test results showing that the numbers of your white blood cells have changed.
  • Restlessness with increased body movement


Legal Differences

Adrafinil verses Provigil (Modafinil) differ in terms of their legal status.

Modafinil is a prescription drug in the United States (Schedule IV). So Modafinil is illegal to possess in the US without a prescription, but prosecutions are rare. Many people in the United States buy Modafinil overseas, however very rarely are parcels are seized at customs. Legal action seems to be rarely (if ever) pursued.

Adrafinil, despite being essentially a prodrug for Modafnil, is unregulated in the US and may be sold as a dietary supplement. Hence, Adrafinil is both less expensive and more readily obtainable, due to the legal risks associated with purchasing Modafinil online.


Chemical NameBenzhydrylsulphinyl-acetohydroxamic Acid
Trade NameOlmifon®
Chemical FormulaC15H15NO3S
Molecular Weight289.351
PatentU.S. - 4,066,686
MechinismAlpha 1 adrenoceptor, Agonist effect
Legal Status (US)Unscheduled, Uncontrolled
Legal Status (EU)Available over the counter (OTC)
Molecular Structure


Where to buy Modafinil

Adrafinil can be purchased online relatively easily, Modafinil will be a little harder to find, please read my article , Where to buy Modafinil, Modalert online



[1]  Mechanisms of modafinil: A review of current research Paul Gerrard and Robert Malcolm

[2] Practical Use and Risk of Modafinil, a Novel Waking Drug Dongsoo Kim

[3] Modafinil-Induced Changes in Functional Connectivity in the Cortex and Cerebellum of Healthy Elderly Subjects. Miriam Punzi1, Tommaso Gili, Laura Petrosini, Carlo Caltagirone, Gianfranco Spalletta, Stefano L. Sensi

[4] Narcolepsy medication modafinil is world’s first safe ‘smart drug’

[5] Cognitive enhancement with methylphenidate and modafinil: conceptual advances and societal implications