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Flmodafinil

Emerging

CRL-40,940 / lauflumide / bisfluoromodafinil — fluorinated modafinil analog reportedly 3-4× more potent with 10-15+ hr duration. Cephalon abandoned…

Aliases (7)

CRL-40940 · CRL-40 · 940 · Lauflumide · bisfluoromodafinil · fluorinated-modafinil · 2-[[bis(4-fluorophenyl)methyl]sulfinyl]acetamide

TYPICAL DOSE

50-100 mg

50-100 mg AM

ROUTE

Oral (capsule)

Oral capsule (research-chem only)

CYCLE

Don't

Don't (use modafinil/armodafinil instead)

STORAGE

Room temp; original container

Room temp

Overview

What is Flmodafinil?

Flmodafinil (CRL-40,940 / lauflumide / bisfluoromodafinil) is a synthetic fluorinated analog of modafinil from the same Lafon/Cephalon CRL-series program that produced modafinil itself. Cephalon explored development as a modafinil successor but abandoned it in favor of armodafinil. It is research-chem only — never FDA-approved and never reached clinical trials.

Key Benefits

Reportedly 3-4× more potent than modafinil mg-for-mg with 10-15+ hour subjective duration via improved BBB penetration from para-fluoro substitution. Unlike fladrafinil, it is the active form directly (not a hepatic prodrug), which means lower interindividual variability and lower hepatic load.

Mechanism of Action

Bisfluoro-substituted modafinil analog — para-fluorine on both phenyl rings raises lipophilicity, improving BBB penetration and reducing required dose. Assumed direct DAT inhibition with downstream orexin/histamine/glutamate cascade analogous to modafinil. Longer apparent duration likely reflects altered clearance kinetics.

Research Indications

Most Effective

Increased lipophilicity

para-fluorine substitution on aromatic rings raises logP, improving membrane permeability and blood-brain barrier penetration. This is th…

Effective

Slower hepatic clearance

fluorine substitution typically slows CYP-mediated oxidative metabolism at the substituted positions, plausibly extending plasma half-lif…

Investigational

Different P450 substrate profile

likely still CYP3A4-dominant (modafinil-class) but with possibly altered fractional contributions from CYP2C19 and other isoforms. No for…

Investigational

Altered DAT-binding affinity

preclinical literature (modafinil-derivative SAR work) suggests fluorinated analogs in this class can have modestly higher DAT affinity t…

Research Protocols

Disclaimer: These are commonly discussed research protocols and not medical advice.

Goal

Dose

Frequency

Solo Use

Cycle

Goal:Cycled use only

Dose:—

Frequency:weekly

Solo:—

Cycle:—

Peptide Interactions

L-theanine 200 mg

Synergistic

same smoothing-the-edge logic as with modafinil. Likely the safest single co-administration.

Caffeine (low dose)

Synergistic

modafinil-class additivity assumed, but flmodafinil's stronger DAT engagement makes the cardiovascular load potentially more relevant. 50-100 mg caffeine cei…

Citicoline / Alpha-GPC

Synergistic

cholinergic substrate support for the cognitive load that modafinil-class drugs let you sustain.

Bromantane

Synergistic

different mechanism, no overlap, plausibly synergistic (same logic as for modafinil/armodafinil). Also research-chem in this combination — additive unknown-u…

Other modafinil-class eugeroics

Avoid

(modafinil, armodafinil, adrafinil, fladrafinil, hydrafinil, solriamfetol, pitolisant) — redundant DAT or wakefulness mechanism plus AUC stacking. Pick one.

Classical stimulants

Avoid

(amphetamine, methylphenidate, focalin, lisdexamfetamine) — overstimulation, cardiovascular load, anxiety, sleep wreck. Possibly worse than with modafinil du…

MAO inhibitors

Avoid

(selegiline >10 mg, tranylcypromine, phenelzine) — hypertensive crisis risk. Hard contraindication.

Hormonal contraceptives

Avoid

assumed CYP3A4 induction (modafinil-class) reduces efficacy ~18%; same partner-relevant caveat.

Yohimbine, high-dose synephrine

Avoid

stacked alpha-1/alpha-2 effects = anxiety + BP spike.

Other CYP3A4 inducers daily

Avoid

(rifampin, St. John's Wort, carbamazepine) — unpredictable plasma flmodafinil reduction.

Cannot reliably define.

Compatible

Without a characterized drug-interaction profile, "neutral" is inference, not knowledge. Assume modafinil's documented interaction set as a starting point.

Quality Indicators

✓

Third-party COA published per batch

Tier-1 research-chem vendors (Kimera Chems, Lordheim, Mountain Pure tier) publish HPLC purity and identity COAs from independent labs. Match the lot number on the COA to the lot on the bottle.

No pharmaceutical reference standard

Even with COAs, there is no pharmaceutical-grade flmodafinil to compare against. Vendor-reported purity is the ceiling; actual content can vary batch-to-batch.

✗

No COA, vague product description, or rotating vendor name

Counterfeit and impurity risk is high in research-chem channels. Vendors that cannot show batch-specific third-party testing should be avoided.

✗

Capsule dose mismatched between vendors

Different vendors sell '50 mg' capsules with materially different actual content. Do not assume equivalence between vendor sources.

What to Expect

Week 1
Tolerability and dose-response.
Week 2-4
Early effect window.
Week 4-8
Peak benefit assessment.
Week 8+
Cycle decision point.

Side Effects & Safety 10

Side Effects

1Headache — reported by users; assumed modafinil-class. Possibly higher frequency than modafinil due to higher effective DAT engagement.
2Reduced appetite — reported, often noted as more pronounced than modafinil.
3Insomnia / shifted sleep onset — bigger concern than modafinil due to extended duration. Late-day dosing strongly inadvisable.
4Anxiety / nervousness — reports mixed; some users describe "calmer than modafinil," others describe stronger jitteriness at modafinil-equivalent doses.
5Nausea, GI upset
6Dry mouth, increased thirst
7Mild HR / BP elevation
8Dizziness
9Skin irritation
10Mood blunting

When to Stop

Stevens-Johnson Syndrome / TEN / DRESS — theoretical risk inherited from modafinil/armodafinil class. Modafinil's labeled SJS rate is roughly 1-3 per million prescriptions; armodafinil added a 2017 FDA SJS warning update. The watch period for flmodafinil is unknown because no surveillance database exists. Treat the modafinil 1-8 week watch period as a floor, not a ceiling. With higher effective DAT engagement and unknown immunogenic profile of the bisfluoro substitution, the risk profile could be similar, lower, or higher — there is no way to know.
Hepatotoxicity — lower expected risk than fladrafinil/adrafinil because flmodafinil is the active form, not a prodrug. LFT monitoring is still prudent given the absence of formal data.
Cardiovascular — assumed modafinil-class (PVCs, BP elevation). Possibly amplified by higher effective DAT engagement at modafinil-equivalent subjective effect.
Psychiatric — assumed modafinil-class (rare psychosis, mania, suicidal ideation). The longer duration could plausibly amplify the psychiatric risk window per dose.
Idiosyncratic reactions — the unknown unknowns. Modafinil's took ~10 years of post-marketing surveillance to map. Flmodafinil's have never been mapped.
Weeks 1-8: rash watch (modafinil-class SJS floor — possibly longer for flmodafinil given lack of data)
Weeks 1-12: liver enzyme watch (lower hepatic load expected vs. fladrafinil but still warranted)
Weeks 1-4: BP / HR watch (modafinil-class with possible amplification)
Indefinite: idiosyncratic reaction watch — there is no established safety boundary

References

Modafinil — Wikipedia 2026

en.wikipedia.org · 2026

primary structural and historical reference for the parent compound; CRL-series development context.

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Lafon Laboratoires — CRL-series program history

en.wikipedia.org

context for the Lafon → Cephalon → Teva development chain that produced modafinil, armodafinil, and the abandoned analogs (CRL-40,940 flmodafinil, CRL-40,941 fladrafinil, CRL-40,028 adrafinil).

View Study