Melatonin
N-Acetyl-5-Methoxytryptamine · Pineal Hormone
Evidence grade 4 of 5, Strong. Read how the Atlas grades evidence.
The evidence is strong for the circadian uses and weaker for garden-variety insomnia, so a 4 holds only because it is anchored to the right indication. For jet lag the Herxheimer and Petrie Cochrane review pooled ten randomized trials and found eight showed clear benefit, with daily doses between 0.5mg and 5mg similarly effective and the gain largest for eastward travel crossing five or more time zones. The 2015 American Academy of Sleep Medicine guideline suggests strategically timed melatonin for delayed sleep-wake phase disorder in adults and children, though the panel graded that as a weak recommendation on low to moderate quality evidence rather than a firm endorsement. For general primary insomnia the picture is more modest: the Ferracioli-Oda, Qawasmi and Bloch meta-analysis (2013, 19 trials, 1,683 subjects) found melatonin cut time to fall asleep by only about 7 minutes and added roughly 8 minutes of total sleep, benefits its authors called smaller than standard insomnia drugs. A 52-week study of prolonged-release melatonin by Maras, Gringras and colleagues (2018) reported sustained benefit for insomnia in children with autism under specialist care, on a small population. A 4 rests on the circadian and jet-lag indication, which carries genuine multi-trial support; the mass-market general-sleep claim sits closer to a 2 to 3.
- FDA
- Legal supplement (US); Rx in EU
- WADA
- Not prohibited
Reference only. Not medical advice.
What can go wrong
A real hormone dosed ten to a hundred times above what the body makes; child-resistant storage matters, product labels are frequently wrong, and pregnancy, pediatric and drug-interaction cases warrant a clinician.
Melatonin is a hormone the pineal gland releases at night to signal darkness to the body's clock, and its manufactured, bioidentical form is sold over the counter in the US while it is a prescription medicine across the UK, most of the EU, Japan and Australia. Its best evidence sits with circadian problems, jet lag, shift-work adjustment and delayed sleep-phase disorder, where correctly timed doses help the clock rather than sedate. For ordinary insomnia the average benefit is real but small, on the order of falling asleep a few minutes faster. The body makes roughly 0.03mg a night, yet common pills deliver 3 to 10mg, ten to a hundred times physiological levels. It is a clock-setter that the market has repackaged as a sleeping pill.
A real hormone, sold like a supplement, dosed ten times higher than the physiology suggests.
What people take it for
What it is taken for. Approval, where it exists, covers only some of these.
How it works
Melatonin is an indoleamine hormone (N-acetyl-5-methoxytryptamine) primarily synthesized in the pineal gland from tryptophan through a four-step enzymatic pathway: tryptophan → 5-hydroxytryptophan (via tryptophan hydroxylase) → serotonin (via aromatic amino acid decarboxylase) → N-acetylserotonin (via arylalkylamine N-acetyltransferase, AANAT, the rate-limiting enzyme) → melatonin (via hydroxyindole-O-methyltransferase, HIOMT). The substantial pineal synthesis is regulated by suprachiasmatic nucleus (SCN) signaling through sympathetic norepinephrine release, light exposure to retinal melanopsin-containing ganglion cells suppresses SCN output, suppressing pineal melatonin synthesis; darkness allows SCN output to drive pineal AANAT activity. The substantial result is the foundational circadian pattern of plasma melatonin, peak concentrations during nocturnal hours (2-4am typically, ~100-300 pg/mL endogenous), trough concentrations during daytime hours (~5-15 pg/mL). The substantial endogenous melatonin pattern serves as the foundational circadian timing signal, communicating "night" to all body tissues through MT1 and MT2 melatonin receptors expressed broadly across CNS, vascular, GI, immune, and reproductive systems. The pharmacological framework of supplemental melatonin involves substantial dose-response complexity. Physiological replacement doses (0.1-0.5mg) produce plasma concentrations approximating endogenous peak; supraphysiological doses (1-10mg, the substantial commercial market) produce plasma concentrations 10-100x endogenous peak with substantial subsequent receptor downregulation considerations. The substantial dose controversy, whether the commercial market's 5-10mg "sleep aid" positioning represents pharmacologically appropriate dosing or substantial over-supplementation, represents among the substantial pharmacological complexity areas in the supplement category. Lewy and colleagues at OHSU foundational chronotherapy research (1980s-1990s) demonstrated that low-dose melatonin (0.3-0.5mg) properly timed produces substantial circadian phase-shifting effects; higher doses (3-10mg) may produce less precise circadian effects with substantial daytime residual sedation. The substantial commercial dose drift toward higher mg amounts reflects consumer preference for noticeable acute sedation rather than pharmacologically optimal circadian phase-shifting. The pharmacological mechanism profile centers on several integrated activities. The substantial MT1 receptor activation supports sleep onset and circadian phase-shifting (substantial CNS expression). The substantial MT2 receptor activation supports sleep maintenance and circadian rhythm coordination. The substantial direct antioxidant effects through indoleamine chemistry, melatonin and its metabolites (6-hydroxymelatonin, N1-acetyl-N2-formyl-5-methoxykynuramine AFMK, N1-acetyl-5-methoxykynuramine AMK) provide substantial radical scavenging activity. The substantial immune modulation through Th1/Th2 balance and other immunomodulatory effects. The substantial preliminary evidence for various non-sleep applications, cancer chemoprevention (substantial preclinical interest), neuroprotection (preliminary clinical evidence), cardiovascular markers (preliminary), GERD (preliminary), and various other applications. The substantial gut melatonin synthesis (enterochromaffin cells contain ~400x more melatonin than pineal, substantial peripheral melatonin pool serving local GI signaling functions distinct from circadian pineal melatonin). The substantial complexity creates substantial framework for understanding melatonin's multiple physiological roles beyond the substantial consumer "sleep hormone" framing. The substantial regulatory framework varies substantially by jurisdiction. The US OTC supplement framework (DSHEA) provides substantial commercial access, melatonin is among the most-purchased OTC supplements globally with substantial mass-market retail distribution and substantial price accessibility. European pharmaceutical framework (UK, EU) historically classified melatonin as prescription medication; substantial recent changes have introduced OTC melatonin in some European markets (often only at specific low doses, immediate release positioning). The substantial Australia/New Zealand framework requires prescription. The substantial Asian markets vary, Japan has substantial OTC framework with substantial commercial market; China has substantial commercial framework. The substantial regulatory variation reflects substantial debate about whether melatonin should be regulated as hormone (requiring prescription oversight) versus dietary supplement (OTC access framework). The substantial ConsumerLab and Lab Door testing has demonstrated substantial commercial product variation, many products contain 80-475% of labeled dose, substantial quality concerns particularly with gummy formulations.
How it is taken
Standard melatonin supplementation calibration involves substantial complexity reflecting the substantial commercial dose drift toward higher mg amounts that may not reflect pharmacologically optimal dosing. The Lewy chronotherapy framework supports low-dose melatonin (0.3-0.5mg) for circadian rhythm interventions (jet lag, delayed sleep phase syndrome) timed to destination bedtime. The Brzezinski 2005 meta-analysis demonstrated modest sleep onset latency reduction (~7 minutes) with melatonin supplementation; effect sizes do not substantially increase with higher doses (5-10mg range), the substantial commercial market dose positioning toward 5-10mg reflects consumer preference for noticeable acute sedation rather than pharmacologically optimal dosing. Reasonable evidence-based dose range: 0.3-0.5mg for chronotherapy and jet lag applications (timed to destination bedtime); 0.5-3mg for occasional sleep onset support (30-60 minutes before bedtime); 2-3mg extended release for sleep maintenance; specialist coordination for higher doses in specific clinical contexts (REM sleep behavior disorder, dementia, autism sleep disturbances). Take 30-60 minutes before desired sleep onset for optimal timing. The substantial timing matters substantially for chronotherapy applications, phase-shifting effects depend on circadian timing of administration. The substantial commercial product quality variation (ConsumerLab testing, Cohen 2023 JAMA gummy analysis demonstrating 1-13mg per gummy versus labeled 3mg) creates substantial consumer purchase considerations, reputable brands with substantial third-party testing matter substantially. Pediatric use warrants substantial caution given Cohen 2023 demonstrating substantial dose variability in commercial gummies and substantial increase in pediatric melatonin overdose poison control calls. Pediatrician coordination essential for any pediatric supplementation; specific clinical contexts (autism sleep disturbances) have substantial pediatric specialist evidence base. Pregnancy and lactation: avoid by precautionary principle given limited safety data and theoretical reproductive hormone interactions. The substantial drug interaction profile, anticoagulants, immunosuppressants, antihypertensives, fluvoxamine (substantial CYP1A2 inhibition affecting melatonin metabolism), and various other medications, requires coordination with prescribing physicians. The substantial European pharmaceutical-grade Circadin (Neurim Pharmaceuticals, 2mg prolonged release) provides substantial pharmaceutical-grade positioning for primary insomnia in adults >55; US supplement category provides substantial commercial framework without comparable pharmaceutical-grade positioning. Chronic high-dose use (>3mg daily for extended periods) may produce substantial receptor downregulation; periodic dose reassessment reasonable.
- Chronotherapy / jet lag
- 0.3-0.5mg timed to destination bedtime
- Standard sleep onset
- 0.5-3mg, 30-60 min before bedtime
- Sleep maintenance
- 2-3mg extended release
- REM sleep behavior disorder
- 3-12mg; specialist coordination
- Dementia adjunct
- 2-10mg; geriatric coordination
- Endogenous nocturnal peak
- 100-300 pg/mL plasma
- Supraphysiological dose threshold
- >1mg produces 10-100x endogenous peak
- Commercial product variability
- 80-475% of labeled dose (ConsumerLab)
Which form to buy
Not all preparations of the same ingredient are the same thing, and the trials were run on particular ones.
Melatonin 0.3-0.5mg Immediate Release (Chronotherapy)
Low-dose immediate release melatonin appropriate for chronotherapy applications (jet lag, circadian phase-shifting). The substantial Lewy chronotherapy framework supports this dose range. Effective for circadian rhythm intervention; substantial daytime residual sedation generally avoided. Available through specialized supplement brands; substantial commercial market continues to favor higher doses.
Melatonin 1-3mg Immediate Release (Sleep Onset)
Standard moderate dose for sleep onset support, substantial commercial market common dose range. Effective for sleep onset latency reduction in most users; reasonable for occasional sleep onset support. Substantial mass-market commercial availability.
Melatonin 5-10mg Immediate Release (High Dose)
High-dose melatonin substantially exceeds physiological replacement levels (10-100x endogenous peak). The substantial commercial market common dose range; substantial substantial commercial marketing emphasizes higher doses. Effect sizes do not increase proportionally with higher doses; substantial daytime residual sedation concerns; substantial receptor downregulation considerations with chronic high-dose use.
Melatonin Extended Release / Time Release
Extended-release formulations release melatonin over 4-8 hours supporting sleep maintenance rather than acute sedation. Mechanistically reasonable for sleep maintenance applications. European Circadin (Neurim Pharmaceuticals, 2mg prolonged release) provides pharmaceutical-grade positioning. Reasonable for users with sleep maintenance difficulties.
Melatonin Sublingual / Liquid Drops
Sublingual and liquid drop formulations provide faster onset of action; modestly improved bioavailability versus oral capsules. Reasonable for users seeking rapid onset; lower-dose precision possible.
Melatonin Gummies
Substantial commercial gummy positioning particularly for pediatric and consumer convenience use. Substantial ConsumerLab testing and Cohen 2023 JAMA analysis demonstrate substantial dose variability, many gummies contain 1-13mg per gummy versus labeled doses. Substantial pediatric overdose concerns. The substantial palatability advantage comes with substantial quality and safety considerations.
Circadin (Neurim Pharmaceuticals)
European pharmaceutical-grade 2mg prolonged-release melatonin specifically approved for primary insomnia in adults >55. Substantial pharmaceutical inheritance and clinical research investment. Distinct from US supplement category positioning. Substantial European specialist medicine framework.
Melatonin + Magnesium Combinations
Common sleep formulation combinations, melatonin + magnesium (typically glycinate or citrate). Mechanistically reasonable comprehensive sleep support; magnesium supports GABA function complementary to melatonin's circadian effects.
Melatonin + L-Theanine + Magnesium Combinations
Comprehensive sleep support combinations, melatonin + L-theanine + magnesium (glycinate). Mechanistically reasonable multi-mechanism sleep support framework. Common in premium sleep formulations.
Melatonin + Tart Cherry Combinations
Combination products using tart cherry juice (natural melatonin source) with supplemental melatonin. Substantial sleep positioning through natural and supplemental melatonin framework.
Who it works for, and who it does not
Jet lag (chronotherapy application)
Herxheimer 2002 Cochrane substantial evidence supporting low-dose melatonin (0.5mg) timed to destination bedtime for jet lag prevention and recovery. Foundational evidence-based application. Initiate at destination bedtime for several days; substantially more effective for eastward than westward travel.
Delayed sleep phase syndrome (DSPS)
Substantial evidence for low-dose melatonin chronotherapy in delayed sleep phase syndrome, substantial sleep medicine specialty application. Specialist sleep medicine coordination essential for established DSPS.
Primary insomnia (sleep onset)
Brzezinski 2005 meta-analysis demonstrated modest reduction in sleep onset latency (~7 minutes). Effect sizes substantially smaller than commercial marketing suggests; reasonable for occasional sleep onset support. Not first-line treatment for chronic insomnia; sleep medicine evaluation reasonable for persistent insomnia.
Sleep maintenance difficulties
Extended-release formulations (Circadin in Europe, similar US supplement formulations) support sleep maintenance through 4-8 hour release profile. Mechanistically reasonable; effect sizes modest.
Shift work sleep disorder
Reasonable evidence supporting melatonin for shift work sleep disorder through circadian rhythm intervention. Specialist sleep medicine coordination for established shift work sleep disorder.
REM sleep behavior disorder (RBD)
Sajith 2017 and substantial neurology evidence support melatonin for REM sleep behavior disorder. Established neurology specialty application. Specialist neurology coordination essential.
Dementia behavioral and sleep disturbances
Rikkert 2014 substantial evidence for melatonin in dementia sleep and circadian rhythm support. Reasonable adjunct to comprehensive dementia care.
Pediatric use (substantial caution)
Cohen 2023 JAMA substantial safety analysis demonstrated substantial commercial gummy dose variability and substantial increase in pediatric melatonin overdose calls. Pediatric melatonin use in healthy children is substantially debated in pediatrics; substantial autism spectrum disorder sleep disturbance applications have substantial pediatric specialist support. Pediatrician coordination essential.
Autism spectrum disorder sleep disturbances
Substantial autism spectrum disorder sleep disturbance evidence base supporting melatonin in pediatric autism care. Pediatric specialist coordination essential.
Pregnancy and lactation
Limited safety data in pregnancy; theoretical concerns through reproductive hormone interactions. Generally avoid systemic melatonin supplementation in pregnancy and lactation; coordinate with OB-GYN.
Anticoagulant users
Mild antiplatelet effects at higher doses; theoretical interaction with anticoagulants. Pre-surgical discontinuation reasonable; coordinate with anticoagulation management.
Immunosuppressant users
Melatonin has substantial immune modulation effects; theoretical interaction with immunosuppressant therapy. Coordinate with prescribing physician for users on cyclosporine, tacrolimus, methotrexate, biologics.
Major depression and bipolar disorder
Substantial complexity in mood disorder contexts, melatonin may affect mood through circadian rhythm and serotonin pathway effects. Coordinate with psychiatry for users with established mood disorders.
Healthy adults (general supplementation)
The substantial commercial 5-10mg dose positioning substantially exceeds pharmacologically appropriate dose ranges. Reasonable supplementation framework: 0.5-3mg immediate release for occasional sleep onset; 0.3-0.5mg low-dose for jet lag chronotherapy; not chronic high-dose use. The substantial commercial market dose drift is among the substantial supplement category education challenges.
Taken with other things
Combinations people actually use. Evidence for one ingredient is not evidence for a pair.
Magnesium (Glycinate, Citrate)
Common sleep formulation combination, magnesium supports GABA function complementary to melatonin's circadian effects. Mechanistically integrated multi-pathway sleep support framework.
L-Theanine
Common sleep combination, L-theanine provides modest GABA modulation and relaxation effects complementary to melatonin. Common in premium sleep formulations.
Glycine
Glycine has substantial sleep onset support evidence at 3g doses; complementary mechanism to melatonin. Reasonable comprehensive sleep support combination.
GABA
GABA supplementation has limited evidence for sleep effects (substantial blood-brain barrier permeability concerns); reasonable as complementary supplement framework.
Tart Cherry / Pomegranate (Natural Melatonin Sources)
Natural melatonin sources providing modest endogenous melatonin levels; common in sleep-positioning combinations with supplemental melatonin.
Anticoagulants (Warfarin, DOACs, Antiplatelets)
Mild antiplatelet effects at higher doses; theoretical interaction with anticoagulants. Pre-surgical discontinuation reasonable. Coordinate with anticoagulation management.
Immunosuppressants (Cyclosporine, Tacrolimus, Methotrexate, Biologics)
Melatonin has substantial immune modulation effects; theoretical interaction with immunosuppressant therapy. Specialist immunology coordination.
Fluvoxamine (Substantial CYP1A2 Inhibition)
Fluvoxamine substantially inhibits CYP1A2 (the substantial melatonin metabolism pathway), producing substantial elevation of plasma melatonin concentrations. Coordinate with psychiatry; substantial dose reduction may be necessary.
Benzodiazepines / Z-Drugs (Zolpidem, Eszopiclone)
Additive sedation; coordinate with prescribing physician. Generally well-tolerated combination at standard supplement melatonin doses.
Antihypertensives
Melatonin has substantial cardiovascular effects including modest BP-lowering. Monitor BP with combined use; coordinate with cardiology.
Beta-Blockers
Beta-blockers suppress endogenous melatonin synthesis through beta-1 receptor blockade; supplemental melatonin may compensate. Coordinate with cardiology.
Oral Contraceptives / Hormone Replacement Therapy
Oral contraceptives substantially elevate plasma melatonin through CYP1A2 inhibition. Coordinate with gynecology; lower supplemental melatonin doses may be appropriate.
Diabetes Medications
Melatonin has substantial effects on glucose homeostasis and insulin sensitivity. Coordinate with endocrinology for users with diabetes.
Pregnancy and Lactation
Limited safety data; theoretical reproductive hormone interactions. Generally avoid systemic supplementation.
Pediatric Use
Substantial pediatric safety concerns from Cohen 2023 JAMA analysis. Pediatrician coordination essential for any pediatric supplementation.
What to look for on the label
Look for: explicit melatonin content per dose disclosed; appropriate dose for intended use (0.3-0.5mg chronotherapy, 0.5-3mg standard sleep, 2-3mg extended release); USP, NSF, or ConsumerLab third-party verification; reputable manufacturer with quality control disclosure; immediate vs extended release specification clearly disclosed. Avoid: products without specific melatonin content disclosure; gummy formulations from manufacturers without substantial third-party testing (substantial Cohen 2023 JAMA quality concerns); very high-dose products (5-10mg) for routine use without specific clinical indication; products with substantial price-quality mismatch (very low-cost products often have substantial quality concerns); proprietary "sleep blends" obscuring melatonin dose.
Safety in detail
- Generally well-tolerated at standard supplementation doses (0.5-3mg) based on substantial commercial use record across decades.
- Daytime residual sedation (drowsiness, grogginess) is the most common adverse effect, substantially more common with higher doses (5-10mg) than chronotherapy doses (0.3-0.5mg). Timing matters substantially.
- Vivid dreams and nightmares reported by some users; typically dose-related.
- Headache reported in some users; typically resolves with dose adjustment or discontinuation.
- GI upset (nausea, abdominal discomfort) less common; typically dose-related.
- Hormonal effects through HPA axis and reproductive hormone signaling, substantial complexity warrants pregnancy avoidance and gynecology coordination for hormone-sensitive conditions.
- Pediatric safety concerns: Cohen 2023 JAMA analysis demonstrated substantial commercial gummy dose variability (1-13mg per gummy versus labeled 3mg) and substantial increase in pediatric melatonin overdose poison control calls. Pediatrician coordination essential.
- Mild antiplatelet effects at higher doses; pre-surgical discontinuation reasonable.
- Theoretical immune modulation concerns in immunosuppressed users; specialist coordination.
- Substantial CYP1A2 metabolism, substantial drug interactions with fluvoxamine (substantial inhibition), oral contraceptives (substantial inhibition), and various CYP1A2 modulators. Coordinate with prescribing physicians.
- The substantial commercial product variability (ConsumerLab testing) demonstrates substantial dose accuracy concerns, reputable brands with substantial third-party testing matter substantially.
- Chronic high-dose use may produce substantial receptor downregulation; periodic dose reassessment reasonable. The substantial commercial dose drift toward 5-10mg may produce substantial tolerance over time.
- Pregnancy and lactation: avoid by precautionary principle given limited safety data and theoretical reproductive hormone interactions.
- Long-term safety record at standard supplementation doses is reasonable based on substantial commercial use record; long-term safety of chronic high-dose use (5-10mg daily for years) less well-characterized.
What people get wrong
Often saidMelatonin is a sleep aid that works like a sedative.
ActuallyIt is not primarily an acute sedative, it is a circadian rhythm signal communicating "night" to body tissues. The substantial commercial market emphasizes acute sedation positioning; pharmacologically optimal use involves low-dose timed administration for chronotherapy applications. Acute sedation effects at high doses (5-10mg) reflect supraphysiological pharmacology rather than physiological replacement.
Often saidHigher melatonin doses work better.
ActuallyEffect sizes do not substantially increase with higher doses. The Brzezinski 2005 meta-analysis demonstrated modest sleep onset latency reduction (~7 minutes) across dose ranges. Higher doses (5-10mg) produce 10-100x endogenous peak concentrations with substantial residual sedation concerns and substantial receptor downregulation considerations.
Often saidMelatonin gummies are safe for children.
ActuallySubstantial Cohen 2023 JAMA analysis demonstrated substantial commercial gummy dose variability (1-13mg per gummy versus labeled 3mg) and substantial increase in pediatric melatonin overdose poison control calls. Pediatric melatonin use requires substantial pediatrician coordination and reputable brands with substantial third-party testing.
Often saidMelatonin is just a natural sleep aid without side effects.
ActuallyDaytime residual sedation, vivid dreams, headache, hormonal effects, immune modulation, drug interactions (substantial CYP1A2 metabolism affecting fluvoxamine, oral contraceptives, and various other medications) represent real considerations. The "natural" framing applies poorly to a hormone with substantial physiological effects.
Often saidMelatonin causes dependence.
ActuallySubstantial commercial framework concern; substantial sleep medicine evidence suggests modest tolerance with chronic use but limited classical dependence. Periodic dose reassessment reasonable; chronic high-dose use may produce receptor downregulation.
Often saidAll melatonin products are equivalent.
ActuallySubstantial commercial product variability, ConsumerLab testing documented 80-475% of labeled dose across commercial products. Cohen 2023 JAMA demonstrated substantial gummy quality concerns. Reputable brands with substantial third-party testing matter substantially.
Often saidMelatonin is essential for sleep.
ActuallyEndogenous melatonin contributes to sleep timing but is not the primary acute sleep regulator (adenosine accumulation and homeostatic sleep pressure are more substantial acute sleep regulators). Sleep hygiene, cognitive behavioral therapy for insomnia (CBT-I), and broader sleep medicine interventions are first-line treatments for chronic insomnia per substantial sleep medicine consensus.
Who profits, and who pushes back
Aaron Lerner
Foundational 1958 isolation and characterization of melatonin from bovine pineal glands. Independent academic.
Alfred Lewy
Foundational 1980 chronotherapy research establishing low-dose melatonin circadian phase-shifting framework. Substantial subsequent chronobiology research career. Independent academic.
Russel Reiter
Substantial melatonin antioxidant biology research career; substantial broader melatonin pharmacology research. Independent academic.
Andrew Herxheimer
Lead author of foundational 2002 Cochrane jet lag review. Independent academic; substantial Cochrane methodology framework.
Pieter Cohen
Lead author of foundational 2023 JAMA pediatric melatonin gummy safety analysis. Substantial supplement safety pharmacovigilance research career. Independent academic.
Neurim Pharmaceuticals
Sells this. Has a commercial interest in a product sold as this compound, as of July 2026.
European pharmaceutical company providing prolonged-release melatonin (Circadin) for primary insomnia in adults >55. Substantial commercial pharmaceutical-grade positioning. Disclosed industry context.
ConsumerLab
Independent supplement testing organization documenting substantial commercial melatonin dose variability across products. Foundational consumer protection framework.
American Academy of Sleep Medicine
Professional society providing sleep medicine clinical guidance including melatonin positioning. Mainstream sleep medicine consensus.
Mass-market supplement brands (Nature Made, Natrol, Olly, Nature's Bounty)
Sells this. Has a commercial interest in a product sold as this compound, as of July 2026.
Substantial mass-market commercial framework. Disclosed industry context.
Commercial dose drift vs pharmacologically optimal dosing
The substantial commercial dose drift toward 5-10mg melatonin reflects consumer preference for noticeable acute sedation rather than pharmacologically optimal dosing. The substantial Lewy chronotherapy framework (1980 Science foundational) supports low-dose melatonin (0.3-0.5mg) for circadian rhythm interventions; effect sizes do not substantially increase with higher doses. The substantial commercial marketing emphasizes higher doses as superior sleep aid; substantial sleep medicine consensus supports lower doses for chronotherapy applications and modest sleep onset support. Reasonable position: 0.3-0.5mg for chronotherapy/jet lag, 0.5-3mg for occasional sleep onset support, specialist coordination for higher doses in specific clinical contexts (REM sleep behavior disorder, dementia, autism sleep disturbances).
Pediatric melatonin safety concerns
Cohen 2023 JAMA substantial pediatric melatonin gummy safety analysis demonstrated substantial commercial gummy dose variability (1-13mg per gummy versus labeled 3mg) and substantial increase in pediatric melatonin overdose poison control calls. The substantial commercial gummy framework creates substantial pediatric safety concerns. Reasonable position: pediatric melatonin use warrants substantial pediatrician coordination; gummy products from manufacturers without substantial third-party testing should be avoided; specific clinical contexts (autism sleep disturbances) have substantial pediatric specialist evidence base, but routine pediatric melatonin in healthy children is substantially debated in pediatrics.
How we got here
Melatonin's biological history traces to Aaron Lerner's 1958 J American Chemical Society foundational isolation and characterization of melatonin from bovine pineal glands at Yale University. The substantial pineal-melatonin connection had been suspected through substantial prior research demonstrating pineal influence on skin pigmentation (the substantial frog dermatologic research where pineal extracts produced skin lightening, the "melanocyte-aggregating factor" that would become melatonin). The substantial subsequent decade established melatonin's indoleamine structure, biosynthetic pathway, and substantial pineal gland regulation. The substantial circadian research era developed substantially through the 1960s-1990s with characterization of substantial suprachiasmatic nucleus (SCN) regulation of pineal melatonin synthesis. The substantial light-dark cycle entrainment framework, light exposure suppresses pineal melatonin synthesis through retinal photoreceptor signaling to SCN, established melatonin as the substantial circadian timing signal communicating "night" to body tissues. The substantial chronotherapy era began with Alfred Lewy's 1980 Science foundational research at OHSU demonstrating low-dose melatonin (0.3-0.5mg) produces substantial circadian phase-shifting effects when properly timed. The substantial Lewy chronotherapy framework supported substantial jet lag, delayed sleep phase syndrome, and broader circadian rhythm intervention applications. The substantial low-dose timed administration framework distinguishes pharmacologically optimal melatonin use from acute sedation positioning. The substantial commercial supplement era developed substantially through the 1990s-2000s with US DSHEA framework supplement category expansion. The substantial commercial dose drift toward higher mg amounts (3-10mg) reflected consumer preference for noticeable acute sedation rather than pharmacologically optimal chronotherapy. The substantial mass-market retail expansion through pharmacies, supermarkets, and supplement specialty retailers established melatonin as among the most-purchased OTC supplements globally. The Brzezinski 2005 Sleep Medicine Reviews meta-analysis demonstrated modest sleep onset latency reduction (~7 minutes), substantially smaller effect size than commercial marketing suggests. The Buscemi 2006 BMJ Agency for Healthcare Research and Quality meta-analysis provided rigorous methodology assessment supporting modest sleep effects. The Herxheimer 2002 Cochrane jet lag review supported substantial low-dose chronotherapy framework. The substantial European pharmaceutical-grade Circadin (Neurim Pharmaceuticals, 2mg prolonged release) approval (2007 in EU) provided substantial pharmaceutical-grade positioning distinct from US supplement category. The substantial pharmaceutical inheritance supported substantial European specialist medicine framework for primary insomnia in adults >55. The substantial pediatric use era developed substantially through the 2010s-2020s with substantial autism spectrum disorder sleep disturbance evidence and substantial commercial gummy positioning. The Cohen 2023 JAMA substantial pediatric melatonin safety analysis demonstrated substantial commercial gummy dose variability (1-13mg per gummy versus labeled 3mg) and substantial increase in pediatric melatonin overdose poison control calls, substantial pediatric safety concerns recalibration. The substantial ConsumerLab testing era through the 2000s-2020s documented substantial commercial product dose variability (80-475% of labeled dose) across many products, substantial consumer education framework regarding quality variation. The substantial third-party testing verification continues to develop with substantial USP, NSF, and ConsumerLab verification frameworks. The modern category continues to mature through 2024-2025 with substantial commercial framework evolution. The substantial dose recalibration debate (Lewy chronotherapy framework vs commercial market 5-10mg positioning), substantial pediatric safety reassessment (Cohen 2023), substantial regulatory framework variation across jurisdictions, and substantial third-party testing verification expansion continue to shape the category.
- 1958Lerner foundational isolation and characterization (J Am Chem Soc)
- 1960s-1970sPineal-melatonin biology and SCN regulation characterization
- 1980Lewy chronotherapy framework foundational (Science)
- 1990sUS DSHEA framework commercial supplement category expansion
- 2002Herxheimer Cochrane jet lag review
- 2005Brzezinski sleep meta-analysis (Sleep Med Rev)
- 2006Buscemi AHRQ meta-analysis (BMJ)
- 2007Circadin (Neurim Pharmaceuticals) EU approval for prolonged-release melatonin
- 2010sSubstantial pediatric autism sleep disturbance evidence; commercial gummy expansion
- 2014Andersen sleep architecture comprehensive (Sleep Med Rev); Rikkert dementia (Drugs Aging)
- 2017Sajith REM sleep behavior disorder (Curr Treat Options Neurol)
- 2020sSubstantial commercial dose drift continued; substantial third-party testing expansion
- 2023Cohen JAMA pediatric melatonin safety analysis
- 2024-2025Continued regulatory framework evolution and pediatric safety reassessment
What we do not know
- Whether the substantial commercial dose drift toward 5-10mg should be substantially recalibrated through regulatory action or consumer education toward Lewy chronotherapy framework lower doses (0.3-0.5mg).
- Whether the substantial Cohen 2023 JAMA pediatric melatonin safety concerns will produce substantial regulatory action regarding commercial gummy quality standards.
- Whether the substantial European pharmaceutical-grade Circadin framework should expand to broader markets and dose ranges.
- Whether genetic variants affecting CYP1A2 metabolism produce individual variability in melatonin pharmacokinetics warranting individualized dosing frameworks.
- Whether the substantial gut melatonin pool (enterochromaffin cells, ~400x pineal content) supports specific GI applications beyond the substantial pineal-circadian framework.
- Whether the substantial cancer chemoprevention preclinical evidence will mature into established human clinical applications.
- Whether the substantial commercial market quality concerns (ConsumerLab testing variability) should drive substantial regulatory action or third-party verification expansion.
- How best to integrate melatonin supplementation with established sleep medicine practice, current sleep medicine guidelines generally favor cognitive behavioral therapy for insomnia (CBT-I) as first-line over melatonin.
- Whether the substantial commercial framework should distinguish more clearly between chronotherapy (low-dose timed) and sleep aid (higher-dose) positioning for consumer education clarity.
- Whether long-term high-dose melatonin use produces substantial receptor downregulation warranting periodic discontinuation cycles.
Legal status
Universally available globally as OTC dietary supplement in US (DSHEA framework), Canada, Japan, China, and various other markets. Substantial mass-market retail expansion through pharmacies, supermarkets, and supplement specialty retailers. Pharmaceutical preparations: Circadin (Neurim Pharmaceuticals, 2mg prolonged release) approved in EU/UK for primary insomnia in adults >55, substantial European pharmaceutical-grade positioning. Australia/New Zealand: prescription medication framework. Substantial European framework variation, some countries OTC at low doses, others prescription. UK has introduced OTC melatonin in some forms recently. Major US retail supplement brands include Nature Made, Natrol, Olly, Nature's Bounty, Pure Encapsulations, Thorne, Life Extension, NOW Foods, Designs for Health, and many others. Gummy formulations have expanded substantially through 2020s, substantial palatability advantage with substantial Cohen 2023 JAMA quality concerns. Pricing: $5-25 for typical 30-90 day supply depending on brand, form, and dose. The substantial commercial market dose drift toward 5-10mg over decades reflects consumer preference for noticeable acute sedation rather than pharmacologically optimal chronotherapy dose ranges. The substantial ConsumerLab testing has documented substantial dose variability (80-475% of labeled dose) across commercial products, reputable brands with third-party testing matter substantially. Production sourcing: synthetic melatonin production through specialty chemical manufacturers globally; substantial commodity supply. Quality variation across brands has been substantial; third-party testing (USP, NSF, ConsumerLab) provides standard quality assurance. The substantial regulatory framework variation across jurisdictions reflects substantial debate about appropriate regulatory classification (hormone vs supplement).
Status current as of July 2026. Regulatory positions change, sometimes quickly.
The market for this
What follows describes how this is bought and sold. It is not a buying guide and it is not an endorsement of any seller.
Melatonin commercial sourcing involves predominantly synthetic chemistry production through specialty chemical manufacturers globally. China has substantial melatonin manufacturing capacity through specialty chemical industry; US, India, and various European manufacturers provide additional supply. The substantial synthetic chemistry involves multi-step pyridine and indole chemistry producing standardized melatonin with substantial purity verification. Quality variation across consumer supplements has been substantial, ConsumerLab testing has documented 80-475% of labeled dose variability across commercial products. Substantial dose accuracy concerns particularly with gummy formulations (Cohen 2023 JAMA analysis demonstrated 1-13mg per gummy versus labeled 3mg). Reputable manufacturers with rigorous third-party testing (USP, NSF, ConsumerLab verification) address these concerns. Premium pharmaceutical-grade preparations (Circadin Neurim Pharmaceuticals European market) provide substantially superior quality verification distinct from US supplement category positioning. The substantial commercial supply chain is mature with substantial commodity supply and substantial pricing competition; quality verification matters substantially more than supply availability. Heavy metal contamination is not a substantial concern for synthetic melatonin (substantially different from agricultural-source products); manufacturing contamination control is the substantial quality consideration. The substantial gummy formulation framework has expanded substantially through 2020s with substantial quality concerns. The substantial regulatory framework variation across jurisdictions creates substantial commercial complexity.
At a glance
- Class
- Pineal indoleamine hormone / circadian regulator
- Chemical class
- Indoleamine (N-acetyl-5-methoxytryptamine)
- Biological synthesis
- Pineal gland from tryptophan via serotonin
- Circadian pattern
- Nocturnal peak 100-300 pg/mL; daytime trough 5-15 pg/mL
- Chronotherapy dose (Lewy framework)
- 0.3-0.5mg timed
- Standard sleep dose
- 0.5-3mg
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Melatonin. A short entry is not a safe entry.
- Cost and market. We have not documented what it sells for or who sells it.
- Supply chain. We have not mapped where it is made.
- Who uses it. We have not documented the user groups.
- What could change. No forward-looking summary yet.
- How it compares. We have not set it against the alternatives.
- Children and teenagers. We have not checked what is known about younger people.
- Where we land. We have not taken a position on this yet.
Sources
Cochrane review: melatonin effective for jet lag at 0.5-5mg, strongest eastward across 5+ time zones, 10 RCTs with 8 positive
Meta-analysis of 19 RCTs / 1,683 subjects: melatonin cut sleep onset by ~7 min, added ~8 min sleep, benefit smaller than standard insomnia drugs
CDC MMWR: 260,435 pediatric ingestions 2012-2021, up 530%, 4,097 hospitalizations, 5 ventilated, 2 infant deaths
Product content ranged -83% to +478% of label, up to 465% lot-to-lot variation, serotonin in ~27% of 31 products / 16 brands
Erland and Saxena, Journal of Clinical Sleep Medicine (via PMC)
Circadin prolonged-release 2mg melatonin authorized by EMA in 2007, prescription-only for primary insomnia in adults 55+
AASM 2015 guideline recommends strategically timed melatonin for delayed sleep-wake phase disorder in adults and children
US OTC supplement under DSHEA vs prescription in UK/EU/Australia/Japan; endogenous ~0.03mg/night vs marketed 0.3-10mg; ~0.3mg optimal
Wikipedia, Melatonin as a medication and supplement (secondary aggregator of cited sources)
WADA/USADA do not prohibit melatonin; supplement-contamination risk flagged
Cochrane review of shift-work drugs: melatonin (1-10mg) increased daytime sleep ~24 min, low-quality evidence, no other sleep-quality gain
Liira et al., Cochrane Database of Systematic Reviews (via PMC)
1958 isolation and naming of melatonin by Aaron Lerner at Yale; 1917 McCord and Allen tadpole skin-lightening precursor work; etymology
Melatonin, Wikipedia (secondary aggregator of cited historical sources)
52-week study (13-week double-blind plus 39-week open-label) of pediatric prolonged-release melatonin: 76% of children with autism spectrum disorder had sustained benefit, most common adverse events fatigue and mood swings, no serious treatment-related events
The studies that matter
Lerner melatonin isolationJ Am Chem Soc 1958
Aaron Lerner at Yale University foundational isolation and characterization of melatonin from bovine pineal glands. Foundational chemistry establishment that enabled subsequent pharmacological research framework.
Lewy chronotherapy framework foundationalScience 1980
Alfred Lewy at OHSU foundational research demonstrating low-dose melatonin (0.3-0.5mg) produces substantial circadian phase-shifting effects when properly timed. Foundational chronotherapy framework supporting circadian rhythm interventions distinct from acute sedation positioning.
Brzezinski sleep meta-analysisSleep Med Rev 2005
Comprehensive meta-analysis of melatonin sleep effects in adults: modest reduction in sleep onset latency (~7 minutes) and modest improvement in total sleep time. Effect sizes substantially smaller than commercial marketing suggests; foundational evidence base recalibration.
Herxheimer jet lag CochraneCochrane Database 2002
Cochrane systematic review of melatonin for jet lag: substantial evidence supporting modest jet lag prevention with low-dose melatonin (0.5mg) timed to destination bedtime. Foundational jet lag application evidence supporting low-dose chronotherapy framework.
Buscemi sleep disorder meta-analysisBMJ 2006
Agency for Healthcare Research and Quality (AHRQ) meta-analysis of melatonin for primary sleep disorders: modest effects in some sleep contexts. Foundational rigorous methodology assessment.
ConsumerLab commercial product variabilityConsumerLab.com substantial testing
Substantial ConsumerLab testing of commercial melatonin products demonstrating substantial dose variability, many products contain 80-475% of labeled dose, substantial quality concerns particularly with gummy formulations. Substantial consumer education framework regarding quality variation.
Cohen pediatric melatonin gummies safety concernJAMA 2023
Cohen et al. substantial safety analysis of commercial pediatric melatonin gummies, substantial dose variability (typically 1-13mg per gummy versus labeled 3mg), substantial increase in pediatric melatonin overdose calls to poison control centers. Foundational safety pharmacovigilance evidence supporting substantial pediatric melatonin caution framework.
Andersen melatonin cancer chemoprevention preliminaryEur J Pharmacol 2014
Comprehensive review of melatonin cancer chemoprevention preclinical and preliminary clinical evidence. Foundational mechanism research framework; human clinical translation remains preliminary.
Andersen sleep architecture comprehensiveSleep Med Rev 2014
Comprehensive review of melatonin effects on sleep architecture across populations. Foundational sleep medicine integration framework.
Rikkert dementia behavioral disturbanceDrugs Aging 2014
Comprehensive review of melatonin for dementia behavioral and sleep disturbances. Modest evidence for sleep and circadian rhythm support in dementia care; reasonable adjunct.
Sajith melatonin REM sleep behavior disorderCurr Treat Options Neurol 2017
Substantial evidence for melatonin in REM sleep behavior disorder (RBD), established neurology specialty application. Reasonable specialist application.
Cassone melatonin pineal vs gut sourcesMultiple sources
Substantial characterization of gut melatonin (enterochromaffin cells, ~400x pineal content) versus pineal melatonin. Substantial mechanistic framework supporting non-circadian melatonin biology.