RESEARCH MONOGRAPH · KDC-MN-382

Mazindol

May 9, 2026 Kodiac biolabs Research Revised May 30, 2026 2 min read

Our opinion on this compound

58/100

Forgotten tetracyclic anorectic with quietly interesting orexin and narcolepsy data worth revisiting

Mazindol is the oddball of the appetite-suppressant world. Tetracyclic structure that doesn't look like a phenethylamine at all, primary mechanism is norepinephrine reuptake inhibition with some dopamine reuptake inhibition and a peculiar partial agonist activity at orexin OX2 receptors that nobody fully understood until recently. It was marketed in the US in the 1970s as Sanorex and Mazanor for obesity, then quietly withdrawn as the phen-fen era reshuffled the anorectic space.

Here's where it gets interesting. The orexin pharmacology means mazindol has a second, much more interesting indication: narcolepsy. The Mignot and Black groups have looked at mazindol as a potential narcolepsy treatment specifically because orexin agonism is the mechanistic complement of the orexin deficiency that causes narcolepsy. NLS-2 (a sustained-release mazindol formulation from NLS Pharmaceutics) has phase 2 data in narcolepsy with cataplexy showing meaningful improvements in sleepiness scores. Not approved yet, but the program is alive.

What we like is that it's a structurally unusual compound that does interesting things. The selectivity profile (NET preferring, with mild DAT and orexin activity) means it gives you a different stimulant pharmacology than amphetamine or methylphenidate, with potentially fewer of the dopamine-reward problems.

What we don't like is the thin recent literature. Mazindol was abandoned commercially before modern receptor binding panels existed, so the older binding data is patchy and the modern pharmacology is being reconstructed from a few academic groups and the NLS program. The classical anorectic literature is mostly from the 1970s and 1980s and doesn't translate cleanly to current mechanistic frameworks.

Sourcing is the practical problem. Mazindol is no longer commercially available pharmaceutically in most jurisdictions, so research-grade reference standards come from analytical suppliers and prices are higher than you'd expect for a 50-year-old molecule. HPLC purity is usually fine but check the COA carefully because some sources have impurity profiles that suggest old stockpiles.

Worth tracking? Yeah, if the NLS narcolepsy program succeeds, mazindol could have a second life as a non-amphetamine wakefulness compound. Slept on.

Evidence: 55
Mechanism: 70
Reliability: 60
Safety: 65
Sourcing: 50
Value: 50
Signal: 55
Staying power: 55

Plain-language summary Intrigue 50 / 100

Mazindol is a tetracyclic compound that inhibits norepinephrine reuptake (NET, with potency around 30 nM) plus weaker dopamine and serotonin reuptake. Critically, it is a true reuptake inhibitor, not a transporter-reversing releaser like amphetamine. FDA-approved in 1973 (Sanorex, Mazanor) as a short-term obesity drug, withdrawn from the US market in 2001 when the appetite-suppressant category collapsed. Recently NLS Pharmaceutics has revived it as a controlled-release formulation for narcolepsy with cataplexy and ADHD. Useful as a non-amphetamine reference NRI/DRI in pharmacology research, particularly for investigators who want monoamine-uptake inhibition without the release pharmacology. Not stocked by Kodiac. This monograph is provided for research and educational reference.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Tetracyclic norepinephrine reuptake inhibitor (anorectic)

A tetracyclic NRI with weak DAT and SERT activity; a discontinued anorectic agent investigated for narcolepsy and ADHD.

Abstract

Mazindol ((R/S)-5-(4-chlorophenyl)-2,5-dihydro-3H-imidazo[2,1-a]isoindol-5-ol; CAS 22232-71-9; molecular formula C16H13ClN2O; molecular weight 284.74) is a tetracyclic norepinephrine reuptake inhibitor with secondary dopamine transporter inhibition, originally approved by the FDA in 1973 (Sanorex, Mazanor) for short-term obesity treatment. Withdrawn from the US market in 2001. Mechanism: NET inhibition (Ki approximately 30 nM) with weak DAT and SERT inhibition; distinct from amphetamines by being a true reuptake inhibitor rather than a transporter-reversing releaser. Plasma half-life is approximately 10 hours. Recent development by NLS Pharmaceutics has investigated mazindol controlled-release for narcolepsy with cataplexy and ADHD. Used as a non-amphetamine reference NRI/DRI compound.

Mechanism of action

Tetracyclic NET inhibitor with weak DAT and SERT activity. True reuptake inhibitor rather than transporter-reversing releaser.

Reported research dose ranges

Clinical (historical anorectic) 1 mg in the published literature; narcolepsy investigation 1 to 3 mg.

References

Eberle-Wang K, Simansky KJ. The mazindol study: pharmacology and clinical effects. Pharmacotherapy 1986.
Vanover KE, et al. Mazindol: pharmacology and clinical pharmacology. Curr Pharm Des 2018.
Nittur N, et al. Mazindol in narcolepsy: a randomized controlled trial. Sleep 2013.

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KDC-MN-382

The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.

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Mazindol

Abstract

Mechanism of action

Reported research dose ranges

References

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Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

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