How long does N-Methylbisfluoromodafinil last?

The total duration of N-Methylbisfluoromodafinil via oral is 5 hours to 8 hours.

N-Methylbisfluoromodafinil

Benzhydryl · Stimulants, Nootropic, Eugeroics

8 dangerous interactions — combining N-Methylbisfluoromodafinil with certain substances may be life-threatening.

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Stimulants, Nootropic, Eugeroics(Benzhydryl)

Quick Dosage

oral100–150 mg (common)

Total duration (oral)5hr–8hr

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N-Methylbisfluoromodafinil (also known as Fluoromodafinil or CRL-40,940) is a synthetic stimulant and eugeroic (wakefulness-promoting) agent of the benzhydryl sulfinyl class — the same structural family as modafinil and adrafinil. It is the N-methyl derivative of bisfluoromodafinil (CRL-40,941, also known as Fladrafinil), itself a bis-fluoro derivative of modafinil. N-Methylbisfluoromodafinil is considered significantly more potent than modafinil — estimated to be 10–40 times more potent by weight — making dosing precision critically important.

The compound is classified simultaneously as a Stimulant, Nootropic, and Eugeroic, reflecting its primary action of promoting wakefulness and cognitive enhancement without the intense euphoria or sympathomimetic cardiovascular effects of classical stimulants. Like modafinil, it is used primarily for wakefulness maintenance, cognitive enhancement, and as a study aid. Community reports describe it as producing alert, focused wakefulness without the "jitteriness" of amphetamines, with a characteristically clean headspace.

However, unlike modafinil — which has decades of clinical use and extensive safety data — N-Methylbisfluoromodafinil has essentially no published human pharmacological studies. Its extremely high potency means that effective doses are measured in single-digit or low double-digit milligrams, creating significant error margin risk from weighing imprecision. The compound is explicitly flagged in PsychonautWiki's data as having an unknown safety profile and should not be assumed safe by analogy to modafinil.

How It Feels

N-Methylbisfluoromodafinil extends the modafinil template with minor pharmacokinetic variations that are difficult to distinguish subjectively. Within one to two hours of oral ingestion, the characteristic eugeroic effect begins to establish itself: a clean, quiet lifting of fatigue that does not feel like stimulation so much as the removal of a weight that had been pressing on consciousness. The mind clears, attention stabilizes, and the world becomes marginally more engageable without becoming more interesting.

At its peak, the experience closely parallels that of armodafinil or modafinil. Wakefulness is sustained and natural-feeling. Concentration improves, and the capacity for extended work sessions increases. There is a calm, patient alertness that permits focus without demanding it. Executive function is gently enhanced, making planning and prioritization feel less effortful. The mood is neutral to slightly positive, though any mood elevation is likely attributable to the satisfaction of functioning well rather than to direct pharmacological euphoria.

Physical effects are minimal and consistent with the modafinil class. Very mild appetite suppression, occasional dry mouth, and a barely perceptible increase in baseline alertness constitute the somatic experience. The body feels normal and functional. There is no cardiovascular stress, no temperature dysregulation, and no peripheral nervous system activation worth mentioning.

Duration may extend somewhat beyond standard modafinil, with users reporting sustained wakefulness for twelve to sixteen hours. This extended duration can be a virtue for shift workers or those with extreme sleep debt to manage, but it can also interfere with sleep if the dose is taken too late in the day. The offset is gradual and gentle. There is no crash, and the return to baseline tiredness is smooth. The compound is, like its parent, a substance defined by what it removes rather than what it adds. The experience is functional, unremarkable, and effective. For those familiar with modafinil, the differences are of degree rather than kind, and the subjective experience may be indistinguishable.

Subjective Effects

The effects listed below are based on the Subjective Effect Index (SEI), an open research literature based on anecdotal reports and personal analyses. They should be viewed with a healthy degree of skepticism. These effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects.

Physical Effects

Physical(8)

Appetite suppression— A distinct decrease in hunger and desire to eat, ranging from reduced interest in food to complete d...
Dehydration— A state of insufficient bodily hydration manifesting as persistent thirst, dry mouth, and physical d...
Dizziness— A sensation of spinning, swaying, or lightheadedness that impairs balance and spatial orientation, o...
Dry mouth— A persistent, uncomfortable reduction in saliva production causing the mouth and throat to feel parc...
Increased heart rate— A noticeable acceleration of heartbeat that can range from a subtle awareness of one's pulse to a fo...
Nausea— An uncomfortable sensation of queasiness and stomach discomfort that may or may not lead to vomiting...
Stimulation— A state of heightened physical and mental energy characterized by increased wakefulness, elevated mo...
Teeth grinding— An involuntary clenching and rhythmic grinding of the jaw muscles, known clinically as bruxism, that...

Cognitive & Perceptual Effects

Cognitive(5)

Anxiety— Intense feelings of apprehension, worry, and dread that can range from a subtle background unease to...
Focus enhancement— An enhanced ability to direct and sustain attention on a single task or stimulus with unusual clarit...
Motivation enhancement— A heightened sense of drive, ambition, and willingness to accomplish tasks, making productive effort...
Thought acceleration— The experience of thoughts occurring at a dramatically increased rate, as if the mind has been shift...
Wakefulness— An increased ability to stay awake and alert without the desire to sleep. Distinct from stimulation ...

Interactions

Substance	Status	Note
25x-NBOH	Dangerous	—
25x-NBOMe	Dangerous	—
Atropa belladonna	Dangerous	Extreme cardiovascular strain from anticholinergic and stimulant effects combined
Datura	Dangerous	Extreme cardiovascular strain from anticholinergic and stimulant effects combined
Diphenhydramine	Dangerous	Extreme cardiovascular strain from anticholinergic and stimulant effects combined
Harmala alkaloid	Dangerous	Risk of hypertensive crisis and serotonin syndrome; potentially fatal combination
Peganum harmala	Dangerous	Risk of hypertensive crisis and serotonin syndrome; potentially fatal combination
MDMA	Unsafe	—
1,3-Butanediol	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
25E-NBOH	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
2C-T	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
2C-T-2	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
2C-T-21	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
2C-T-7	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
3-FMA	Caution	Increased cardiovascular strain and neurotoxicity risk
4-MMC	Caution	Increased cardiovascular strain and neurotoxicity risk
8-Chlorotheophylline	Caution	Increased cardiovascular strain and neurotoxicity risk
Adrafinil	Caution	Increased cardiovascular strain and neurotoxicity risk
Allylescaline	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Ayahuasca	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Benzydamine	Caution	Increased cardiovascular strain and neurotoxicity risk
Bromantane	Caution	Increased cardiovascular strain and neurotoxicity risk
Cake	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Deschloroetizolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Desomorphine	Caution	Stimulants mask opioid sedation, increasing overdose risk when the stimulant wears off
DET	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Dichloropane	Caution	Increased cardiovascular strain and neurotoxicity risk
Diclazepam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
DiPT	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
DOM	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
DPT	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Efavirenz	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Ephedrine	Caution	Increased cardiovascular strain and neurotoxicity risk
EPT	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Eszopiclone	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Etizolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Flubromazepam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Flubromazolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Flunitrazepam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Flunitrazolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Gaboxadol	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Hexedrone	Caution	Increased cardiovascular strain and neurotoxicity risk
Ibogaine	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Lorazepam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Mephenaqualone	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
MET	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Methallylescaline	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Methcathinone	Caution	Increased cardiovascular strain and neurotoxicity risk
Metizolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Midazolam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
MiPT	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
MPT	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Naloxone	Caution	Stimulants mask opioid sedation, increasing overdose risk when the stimulant wears off
Nicotine	Caution	Increased cardiovascular strain and neurotoxicity risk
Nifoxipam	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Oxiracetam	Caution	Increased cardiovascular strain and neurotoxicity risk
Pentobarbital	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Phenobarbital	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Phenylpiracetam	Caution	Increased cardiovascular strain and neurotoxicity risk
Psilocybin Mushrooms	Caution	Increases anxiety, cardiovascular stress, and psychological intensity
Rhodiola Rosea	Caution	Increased cardiovascular strain and neurotoxicity risk
SAMe	Caution	Masks the effects of each drug; risk of overdosing when one wears off before the other
Alcohol	Uncertain	—

Showing 63 key interactions out of 64 total.

Toxicity & Safety

Unknown Safety Profile

N-Methylbisfluoromodafinil has no published human safety data. The PsychonautWiki documentation explicitly states it should not be assumed safe. Any risk characterization is purely inferential from structural class.

Potency-Amplified Risks

The compound's high potency amplifies any adverse effects from accidental overdose. Imprecise weighing — easily achievable with standard milligram scales that are not accurate below 10mg — can result in doses far exceeding therapeutic intent. A 0.01g weighing error can represent 50–100% dose error at intended dosing levels.

Cardiovascular Risk

By modafinil analogy, sympathomimetic cardiovascular effects (elevated heart rate, blood pressure) are possible, particularly at higher doses. The N-methyl modification and fluorine substitutions may alter this profile compared to modafinil.

Hepatotoxicity

Adrafinil — a related benzhydryl sulfinyl compound — is associated with elevated liver enzymes with chronic use. Whether this risk is shared by N-Methylbisfluoromodafinil is unknown. Periodic liver function monitoring with regular use is prudent.

Psychological Risks

As a wakefulness-promoting agent, chronic use disrupts sleep architecture. Sleep deprivation is itself a significant health hazard with cognitive and physical consequences.

Unknown Long-Term Risks

With essentially no human data, the long-term safety of this compound is entirely unknown. This is a fundamental constraint that cannot be overcome by analogy to modafinil.

Addiction Potential

mildly addictive with a low potential for abuse

Overdose Information

Stimulant overdose from N-Methylbisfluoromodafinil is a medical emergency primarily involving cardiovascular and neurological toxicity.

Signs of overdose: Extremely rapid or irregular heartbeat, chest pain, severe headache, dangerously elevated body temperature, seizures, agitation progressing to psychosis, confusion, and loss of consciousness.Emergency response:

Call emergency services immediately
Keep the person cool (remove excess clothing, apply cool water)
If seizures occur, protect the head and clear the area of hard objects
If the person loses consciousness, place in recovery position
Do not give the person more stimulants, caffeine, or depressants unless directed by medical professionalsPrevention: Pre-measure doses. Avoid redosing. Stay hydrated (but don't overhydrate). Take breaks from physical activity. Monitor heart rate if possible. Have someone present who can recognize warning signs.

Full	develops with prolonged and repeated use
Half	3 - 7 days
Zero	1 - 2 weeks

N-Methylbisfluoromodafinil

Quick Dosage

Dosage

oral

Duration

How It Feels

Subjective Effects

Physical Effects

Physical(8)

Cognitive & Perceptual Effects

Cognitive(5)

Pharmacology

Mechanism of Action

Receptor Profile

Pharmacokinetics

Potency Warning

Detection Methods

Urine Detection

Blood and Serum Detection

Standard Drug Panel Inclusion

Confirmatory Methods

Reagent Testing (Harm Reduction)

Interactions

History

Modafinil Scaffold Research

CRL Compound Series

Research Chemical Market

Harm Reduction

Use a Precision Scale

Start Extremely Low

Limit Use Frequency

Monitor for Liver Symptoms

Do Not Combine with MAOIs or Other Stimulants

Accept Uncertainty

Toxicity & Safety

Unknown Safety Profile

Potency-Amplified Risks

Cardiovascular Risk

Hepatotoxicity

Psychological Risks

Unknown Long-Term Risks

Addiction Potential

Overdose Information

Dangerous Interactions

Tolerance

Cross-tolerances

Legal Status

Experience Reports (2)

Tips (4)

See Also

References (3)

Frequently Asked Questions