Key findings
As a sleeping aid, melatonin helps only a little: on average people fall asleep about 7 minutes sooner and sleep about 8 minutes longer.
In 19 RCTs (n = 1,683) of primary sleep disorders, sleep-onset latency fell by 7.1 min (95% CI 4.4–9.8) and total sleep time rose by 8.3 min (95% CI 1.7–14.8), with a small gain in sleep quality (SMD 0.22) that did not fade with continued use. A 2022 network meta-analysis of insomnia drugs found no overall material benefit for melatonin. A 2022 PSQI meta-analysis (23 RCTs) found −1.24 points overall but −0.67 in sleep disorders, with I² = 81%.14
Limits Trials vary widely in dose, timing and population; most are short. Pooled effects hide a subgroup (late body clocks) that benefits more.
Sleep-medicine guidelines do not recommend melatonin for long-term insomnia; a structured talking therapy called CBT-I is the first choice.
The AASM 2017 guideline suggests clinicians not use melatonin for sleep-onset or sleep-maintenance insomnia (WEAK). The European Insomnia Guideline 2023 rates fast-release melatonin as not recommended (grade A). It allows prolonged-release melatonin for up to 3 months only in people aged 55 or over (grade B). The ACP and European guidelines make CBT-I first-line.57
Limits Recommendations are about chronic insomnia disorder, not about circadian timing problems, where melatonin has separate guideline support.
Taken in the early evening, melatonin can move a late body clock earlier; taken in the morning it can move it later, so timing matters more than dose.
The melatonin phase-response curve is roughly 12 h out of phase with light's. In a lab study (n = 34), 0.5 mg gave a maximum advance of about 1.5 h when taken about 3.3 h (2–4 h) before dim-light melatonin onset (DLMO), or 9–11 h before mid-sleep. A dose at bedtime had only a minor phase effect. In delayed sleep phase syndrome, the earlier the dose before DLMO (1.5–6.5 h), the larger the advance (r² = 0.94).810
Limits DLMO is not measured in the app; estimating it from bedtime is imprecise. Evening melatonin is the wrong direction for people whose clock already runs early (early-morning waking).
For shifting the body clock, a low dose such as 0.5 mg works about as well as larger doses, and larger doses are more likely to linger into the morning.
0.5 mg and 3.0 mg produced similar maximum phase shifts (the 0.5 mg optimum fell about 2 h later). A blind man was entrained by 0.5 mg but not by 20 mg, which the authors attributed to spillover onto the wrong part of the phase-response curve. In older poor sleepers, 0.3 mg restored sleep efficiency, while 3 mg caused hypothermia and kept melatonin raised into daylight.91112
Limits Based on small lab studies. For the sleep-promoting (not clock-shifting) effect, a dose-response meta-analysis found effects grow up to about 4 mg/day.
For simply helping sleep come sooner, studies suggest the effect grows with dose only up to a few milligrams and is larger when taken a few hours before bed rather than right at bedtime.
A dose-response meta-analysis of 26 RCTs (1,689 observations) found sleep-latency and total-sleep effects peak around 4 mg/day. Insomnia status and a longer gap between dose and sleep predicted larger latency reductions; the authors suggest about 3 h before the desired bedtime. The 2013 meta-analysis also found larger effects with higher doses and longer trials.11314
Limits Meta-regression across heterogeneous trials, not head-to-head dose comparisons. Higher doses raise side-effect rates and are prescription-only in some countries. This is not a reason for the app to suggest higher doses.
Specialists use carefully timed melatonin, together with a fixed sleep schedule, for people whose body clock runs several hours late; it is not advised for older adults with dementia.
The AASM 2015 guideline gives a second-tier (weak) endorsement to strategically timed melatonin for delayed sleep-wake phase disorder (DSWPD), blind adults with non-24 rhythm, and children with irregular rhythm and neurological disorders. It recommends against melatonin in elderly people with dementia. A DSWPD meta-analysis (91 adults, 226 children) found DLMO advanced 1.18 h, sleep onset 0.67 h earlier and latency 23 min shorter. In an RCT of 116 confirmed DSWPD patients, 0.5 mg taken 1 h before desired bedtime plus a fixed bedtime brought sleep onset 34 min earlier than placebo (95% CI −60 to −8).1517
Limits DSWPD is a clinical diagnosis; in the RCT, benefit was mostly via sleep promotion and DLMO change was not significant in the subset tested. A late bedtime alone is not DSWPD.
Melatonin supplements often don't contain what the label says, so the real dose can be much lower or higher than expected.
In 31 Canadian products, melatonin ranged from −83% to +478% of the label. More than 71% were outside ±10%, lots of the same product varied by up to 465%, and 26% contained serotonin. Of 25 US gummies, only 3 were within ±10%. They ranged from 74% to 347% of the label (1.3–13.1 mg per serving), one had no detectable melatonin, and five contained CBD.1820
Limits Snapshot testing of specific products and lots; quality may differ for pharmaceutical-grade (prescription) melatonin and USP-verified products.
Melatonin gummies are a common cause of accidental poisoning in young children, so keep any supplement out of children's reach and don't give melatonin to a child without a clinician's advice.
US poison centres recorded 260,435 paediatric melatonin ingestions in 2012–2021, a 530% rise. Over the decade there were 4,097 hospitalisations, 287 ICU admissions, 5 children ventilated and 2 deaths, with causation unclear. In 2019–2022 there were an estimated 10,930 ED visits for unsupervised ingestion by children aged 5 or under, 7.1% of all such medication visits; about half involved gummies or other flavoured products.2023
Limits Surveillance data from the US; most ingestions caused no or minor symptoms.
Melatonin is sold freely as a supplement in the US, but it is prescription-only in the UK and, apart from one pharmacist-only product for people 55 and over, in Australia.
In the US melatonin is a dietary supplement with looser FDA oversight than drugs. In the UK it is prescription-only, licensed mainly for short-term sleep problems at 55 or over. In Australia it is Schedule 4; the exception is Schedule 3 (pharmacist-only) 2 mg modified-release tablets for short-term primary insomnia at 55 or over, as monotherapy, in packs of 30 or fewer. In the EU, 2 mg prolonged-release melatonin is a prescription medicine, low-dose food supplements are legal in many states, and EU claims allow 'time to fall asleep' at 1 mg and jet lag at 0.5 mg.2327
Limits EU national rules differ and change (some states ban melatonin in supplements). Check current national rules before region-specific copy.
Short-term melatonin use in healthy adults is generally well tolerated; the commonest side effects are next-day sleepiness, headache and dizziness, and long-term safety is less well studied.
Across 37 RCTs (0.15–12 mg, mostly 4 weeks or less), the commonest adverse events were daytime sleepiness (1.66%), headache (0.74%), dizziness (0.74%) and hypothermia (0.62%), with no serious events identified. In trials of 10 mg or more, drowsiness, headache and dizziness were more frequent than with placebo (RR 1.40), with no detectable rise in serious events.142328
Limits Poor adverse-event reporting in many trials and scarce long-term data; does not cover children, pregnancy or people with chronic illness.
Check with a doctor or pharmacist before trying melatonin if you are pregnant, breastfeeding, under 18, take other medicines, or have epilepsy, an autoimmune condition, or liver or kidney disease.
The NHS lists caution with liver or kidney problems and autoimmune conditions, and says it is not usually recommended in pregnancy. ANSES advises children, adolescents, pregnant and breastfeeding women, people with inflammatory or autoimmune disease, and anyone needing sustained alertness to avoid melatonin supplements. It advises people with epilepsy, asthma or mood disorders, or on any medication, to seek medical advice first. NCCIH flags epilepsy and blood thinners.232427
Limits Precautionary advice largely based on mechanism, case reports and absent data rather than trials showing harm.
Don't combine sleep supplements with sleeping pills, other sedating medicines or alcohol, or stack several sleep supplements together, unless a clinician has said it's fine.
Prolonged-release melatonin 2 mg did not impair performance alone but worsened zolpidem's psychomotor and driving impairment in adults aged 55 and over (n = 16, crossover). The NHS lists interactions with fluvoxamine, benzodiazepines, Z-drugs, opioids, warfarin, carbamazepine and oestrogens, and advises against sedating herbal remedies with melatonin. The TGA limited pharmacist supply to monotherapy, and ANSES advises against combining supplements.24252729
Limits Formal interaction trials exist for few combinations; advice is precautionary for the rest.
Magnesium might help some people fall asleep a little faster, but the evidence is low-certainty and it is not an established treatment for insomnia.
A meta-analysis of 3 RCTs (151 older adults) found sleep onset 17.4 min faster than placebo (95% CI −27.3 to −7.4), a non-significant 16 min more total sleep, and low to very low quality evidence. The main trial gave 500 mg/day for 8 weeks (n = 46). A 2023 review found observational links but contradictory RCTs. A 2026 review of 12 RCTs found inconsistent results with low to very low certainty and said the evidence does not support routine use for insomnia.3033
Limits Older-adult trials at moderate-to-high risk of bias; the 500 mg dose exceeds the US upper limit for supplemental magnesium. People with low dietary magnesium may be the ones who benefit.
One trial found magnesium glycinate slightly eased insomnia symptoms after four weeks; there is no evidence it works better than other forms of magnesium.
In 155 adults with self-reported poor sleep, bisglycinate (250 mg elemental magnesium a day) lowered Insomnia Severity Index scores by 3.9 points, against 2.3 with placebo, at week 4 (p = 0.049, Cohen's d = 0.2). Exploratory analyses suggested larger effects in people with low dietary magnesium intake.34
Limits Single trial, subjective outcomes only, borderline significance; one author runs a contract research organisation funded by supplement companies. No head-to-head comparison of magnesium forms for sleep.
Claims that magnesium L-threonate boosts deep sleep come from small, industry-linked studies with mixed results.
A 21-day RCT (n = 80, 1 g/day) reported better Oura-ring deep and REM sleep scores; some authors were employed by the ingredient supplier. A 6-week RCT (n = 100, 2 g/day, funded by the IP owner) found some subjective sleep improvements but no ring-measured sleep differences.3536
Limits Consumer-wearable sleep staging is not validated against polysomnography for these outcomes.
Keep supplemental magnesium at or below 350 mg a day unless a clinician advises more; people with kidney disease should ask first.
The US Tolerable Upper Intake Level for supplemental magnesium is 350 mg/day for adults (food magnesium is not limited). High doses cause diarrhoea, nausea and cramps. Toxicity risk rises with impaired kidney function. Magnesium reduces absorption of oral bisphosphonates and of tetracycline and quinolone antibiotics, so doses should be separated by about 2 h. US Supplement Facts labels state elemental magnesium.37
Limits Reference value for healthy people; does not cover kidney disease, where any supplement needs medical advice.
Glycine taken before bed has improved how rested people felt in a few small studies, but the evidence is thin.
Small Japanese studies by researchers linked to the manufacturer found that 3 g of glycine at bedtime improved subjective sleep quality, with some polysomnographic changes. Rat studies suggest it lowers core temperature via NMDA receptors in the suprachiasmatic nucleus.3839
Limits Very small samples, short duration, industry involvement; no independent replication or meta-analysis.
L-theanine, an amino acid found in tea, may modestly improve how well people feel they slept, but most studies are small and many used mixed products.
A 2025 meta-analysis (19 studies, N = 897) found improvements in subjective sleep-onset latency (SMD 0.15), daytime dysfunction (SMD 0.33) and overall subjective sleep quality (SMD 0.43). Many trials did not test pure L-theanine. A separate review favoured 200–450 mg/day.4041
Limits Subjective outcomes, few insomnia-diagnosed samples, combination products.
Valerian and chamomile are traditional sleep remedies, but trials have not shown reliable improvements in measured sleep, and guidelines do not recommend valerian.
In 18 RCTs, valerian did not change sleep latency (+0.7 min, 95% CI −3.4 to 4.8) or quantified sleep quality; only a yes/no improvement rating favoured it (RR 1.37). In 14 herbal RCTs for insomnia (n = 1,602), no herb beat placebo on any outcome. A broader review was more positive and attributed inconsistency to extract quality. For chamomile, pooled small trials showed better sleep quality (SMD −0.73), but the one insomnia RCT was null.564246
Limits Products vary widely in composition. People allergic to ragweed-family plants may react to chamomile.
A specific oral lavender-oil product improved sleep in people with anxiety, mainly by easing the anxiety itself.
Silexan 80 mg/day improved anxiety (HAMA −3.83 points against placebo) and PSQI sleep in 697 patients with subthreshold anxiety across 3 RCTs, without sedation. A mediation analysis found more than 98% of its sleep effect ran through reduced anxiety. Lavender essential-oil interventions, mostly inhaled, showed SMD −0.56 on sleep quality in 11 small RCTs.4749
Limits Silexan trials are largely manufacturer-sponsored and results do not generalise to other lavender products; aromatherapy trials are small and hard to blind.
Ashwagandha showed a small benefit for sleep in a handful of trials, but rare liver injury has been reported, so it is not a casual add-on.
Five RCTs (n = 400) found a small-to-moderate effect on overall sleep (SMD −0.59). The effect was larger in diagnosed insomnia, at 600 mg/day or more and over 8 weeks or more. Case series report cholestatic liver injury with jaundice after 2–12 weeks of use, which resolved over 1–5 months.5051
Limits Few, short trials; long-term safety data are limited; liver evidence is case-level.
Tart cherry juice has shown small sleep improvements in a few small studies; it is not a substitute for proven sleep habits.
In a 20-person crossover, 7 days of tart cherry concentrate raised urinary melatonin and actigraphic total sleep time. A 2025 systematic review found only 7 small, heterogeneous interventional studies and called the evidence limited.5253
Limits Small, short trials; sugar content of juices; no standardised dose.
There is not enough evidence that CBD or oral GABA supplements improve sleep.
A systematic review found insufficient evidence for cannabinoid therapies in any sleep disorder. In a pilot RCT (n = 30), 150 mg CBD nightly was similar to placebo on most insomnia outcomes. NCCIH notes possible liver injury, male reproductive harm and drug interactions with CBD. A review of 14 trials found very limited evidence that oral GABA benefits sleep.19465456
Limits Few, small, biased trials; CBD product content is unregulated and some melatonin gummies contain undeclared or declared CBD.
Over-the-counter sleep aids such as diphenhydramine or doxylamine stop working well within days and are not advised for regular use, especially in older adults.
The AASM suggests not using diphenhydramine for insomnia, and the European guideline rates antihistamines as not recommended (A). Tolerance to diphenhydramine's sedation was complete by day 4 (50 mg twice daily, n = 15). The AGS Beers Criteria list first-generation antihistamines as potentially inappropriate in older adults. Higher cumulative anticholinergic use was associated with dementia (HR 1.54 above 1,095 standard daily doses). Doxylamine beat placebo for acute treatment in a 2022 network meta-analysis.465761
Limits The dementia association is observational, and in a large UK study the significant classes were not antihistamines. Short-term occasional use is a different question from nightly use.
If poor sleep lasts more than a few weeks, or comes with loud snoring, breathing pauses, restless legs or low mood, talk to a doctor rather than adding supplements.
US nighttime sleep-aid labels must say to consult a doctor if sleeplessness persists for more than 2 weeks, because 'insomnia may be a symptom of serious underlying medical illness'. The ACP and European guidelines recommend CBT-I as first-line treatment for chronic insomnia. The European guideline calls for polysomnography when other sleep disorders are suspected.6762
Limits Thresholds are pragmatic; this is safety framing, not a diagnostic rule.
What experts and guidelines say
- AASM, chronic insomnia drugs (Sateia, Buysse, Krystal, Neubauer, Heald, 2017): suggests clinicians not use melatonin, diphenhydramine, tryptophan or valerian for sleep-onset or sleep-maintenance insomnia (all WEAK).5
- AASM, intrinsic circadian rhythm disorders (Auger, Burgess, Emens et al., 2015): strategically timed melatonin is endorsed at second-tier confidence for DSWPD, blind adults with non-24, and children with irregular rhythm and neurological disorders. It recommends against melatonin in elderly patients with dementia.15
- European Insomnia Guideline 2023 (Riemann, Espie, Spiegelhalder and 40+ authors): CBT-I first-line (A). Prolonged-release melatonin up to 3 months in people aged 55 and over (B). Antihistamines, fast-release melatonin, ramelteon and phytotherapeutics not recommended (A).6
- ACP 2016 (Qaseem et al.): CBT-I for all adults with chronic insomnia (strong). Medication only by shared decision when CBT-I has failed.7
- AASM health advisory on melatonin in children (2022): talk to a paediatric clinician first. Many child sleep problems respond better to schedule and behaviour changes. If melatonin is used, pick a USP-verified product.20
- NHS / UK: prescription-only. Caution with liver or kidney disease and autoimmune conditions. Long interaction list. Avoid sleepy-making herbal remedies with it. Not usually recommended in pregnancy.24
- TGA (Australia): pharmacist-only only for 2 mg MR, 55+, short-term, monotherapy. The advisory committee noted the data do not support combination with other hypnotics and recommended a maximum of three weeks.25
- ANSES (France, 2018): children, adolescents, pregnant and breastfeeding women, people with inflammatory or autoimmune disease, and anyone needing sustained alertness should avoid melatonin supplements. People with epilepsy, asthma or mood disorders, or on any medication, should ask a doctor first. Keep use occasional and avoid stacking supplements.27
- NIH ODS (magnesium): UL 350 mg/day supplemental. Interactions with bisphosphonates and antibiotics. Kidney impairment raises the toxicity risk.37
- NCCIH: short-term melatonin "appears to be safe for most people", but long-term data are lacking. Evidence for valerian is inconsistent and for chamomile not conclusive. Kava carries a liver-injury risk. Cannabinoids have insufficient evidence.2346
- Named researchers: Helen Burgess and Charmane Eastman (melatonin phase-response curves); Alfred Lewy (the PRC, low-dose entrainment); Shantha Rajaratnam and Tracey Sletten (DSWPD RCT); Debra Skene (melatonin meta-analyses); Pieter Cohen (supplement label accuracy); Adrian Lopresti (magnesium trials and review, with disclosed industry ties).
Myths and overstatements
- Overstated
“Melatonin is a natural sleeping pill that knocks you out.”
On average it shortens sleep onset by about 7 minutes and adds about 8 minutes of sleep. Its clearer role is as a timing signal for a late body clock.159
- Overstated
“If a low dose of melatonin doesn't work, take a bigger one.”
Clock shifts are no larger at 3 mg than at 0.5 mg, and high doses can spill into the wrong part of the phase-response curve. Side effects rise at 10 mg or more, and the sleep-promoting effect plateaus around 4 mg.9111314
- False
“The dose on a melatonin label is what you get.”
Tested products ranged from −83% to +478% of the label, and only 3 of 25 US gummies were within ±10%.1819
- False
“Melatonin is natural, so it's safe to give children.”
Paediatric ingestions rose 530% in a decade, with ICU admissions. Paediatric dosing and long-term effects are uncertain, and the AASM advises asking a paediatric clinician first.2022
- Overstated
“Most poor sleepers are magnesium-deficient, and magnesium fixes insomnia.”
RCTs are few, small and inconsistent, with low to very low certainty. Reviews do not support routine use for insomnia.303233
- Unproven
“Magnesium glycinate is the best form of magnesium for sleep.”
There is one RCT with a small effect (d = 0.2) and no head-to-head comparison between forms.34
- Unproven
“Magnesium L-threonate boosts deep sleep.”
The positive trial used consumer-ring sleep-stage scores and was industry-linked. A second funded trial found no ring-measured sleep difference.3536
- Overstated
“Valerian is a proven herbal sleeping pill.”
Meta-analysis found no effect on sleep latency or quantified sleep quality, and the AASM recommends against it.54243
- Unproven
“CBD helps you sleep.”
There is insufficient evidence in any sleep disorder, and a pilot insomnia RCT found it similar to placebo on most outcomes.5455
- Overstated
“Tart cherry juice is a natural melatonin source that fixes sleep.”
The evidence is a handful of small, heterogeneous studies.5253
- False
“Over-the-counter sleep aids are harmless because you can buy them freely.”
Tolerance to diphenhydramine's sedation develops within about 3–4 days. First-generation antihistamines are on the Beers list for older adults because they are anticholinergic, and guidelines recommend against them for insomnia.565759
References
- 1
Ferracioli-Oda E, Qawasmi A, Bloch MH (2013). Meta-analysis: melatonin for the treatment of primary sleep disorders. PLoS One.
- 2
Auld F, Maschauer EL, Morrison I, Skene DJ, Riha RL (2017). Evidence for the efficacy of melatonin in the treatment of primary adult sleep disorders. Sleep Medicine Reviews.
- 3
Fatemeh G, Sajjad M, Niloufar R, Neda S, Leila S, Khadijeh M (2022). Effect of melatonin supplementation on sleep quality: a systematic review and meta-analysis of randomized controlled trials. Journal of Neurology.
- 4
De Crescenzo F, D'Alò GL, Ostinelli EG, et al (2022). Comparative effects of pharmacological interventions for the acute and long-term management of insomnia disorder in adults: a systematic review and network meta-analysis. The Lancet.
- 5
Sateia MJ, Buysse DJ, Krystal AD, Neubauer DN, Heald JL (2017). Clinical Practice Guideline for the Pharmacologic Treatment of Chronic Insomnia in Adults: An American Academy of Sleep Medicine Clinical Practice Guideline. Journal of Clinical Sleep Medicine (AASM).
- 6
Riemann D, Espie CA, Altena E, et al (2023). The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023. Journal of Sleep Research 32(6):e14035.
- 7
Qaseem A, Kansagara D, Forciea MA, Cooke M, Denberg TD; Clinical Guidelines Committee of the American College of Physicians (2016). Management of Chronic Insomnia Disorder in Adults: A Clinical Practice Guideline From the American College of Physicians. Annals of Internal Medicine 165(2):125-133.
- 8
Lewy AJ, Bauer VK, Ahmed S, et al (1998). The human phase response curve (PRC) to melatonin is about 12 hours out of phase with the PRC to light. Chronobiology International.
- 9
Burgess HJ, Revell VL, Molina TA, Eastman CI (2010). Human phase response curves to three days of daily melatonin: 0.5 mg versus 3.0 mg. Journal of Clinical Endocrinology & Metabolism.
- 10
Mundey K, Benloucif S, Harsanyi K, Dubocovich ML, Zee PC (2005). Phase-dependent treatment of delayed sleep phase syndrome with melatonin. Sleep.
- 11
Lewy AJ, Emens JS, Sack RL, Hasler BP, Bernert RA (2002). Low, but not high, doses of melatonin entrained a free-running blind person with a long circadian period. Chronobiology International.
- 12
Zhdanova IV, Wurtman RJ, Regan MM, Taylor JA, Shi JP, Leclair OU (2001). Melatonin treatment for age-related insomnia. Journal of Clinical Endocrinology & Metabolism.
- 13
Cruz-Sanabria F, Bruno S, Crippa A, et al (2024). Optimizing the Time and Dose of Melatonin as a Sleep-Promoting Drug: A Systematic Review of Randomized Controlled Trials and Dose-Response Meta-Analysis. Journal of Pineal Research.
- 14
Menczel Schrire Z, Phillips CL, Chapman JL, et al (2022). Safety of higher doses of melatonin in adults: A systematic review and meta-analysis. Journal of Pineal Research.
- 15
Auger RR, Burgess HJ, Emens JS, Deriy LV, Thomas SM, Sharkey KM (2015). Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: Advanced Sleep-Wake Phase Disorder (ASWPD), Delayed Sleep-Wake Phase Disorder (DSWPD), Non-24-Hour Sleep-Wake Rhythm Disorder (N24SWD), and Irregular Sleep-Wake Rhythm Disorder (ISWRD). An Update for 2015. J Clin Sleep Med (American Academy of Sleep Medicine).
- 16
van Geijlswijk IM, Korzilius HP, Smits MG (2010). The use of exogenous melatonin in delayed sleep phase disorder: a meta-analysis. Sleep.
- 17
Sletten TL, Magee M, Murray JM, et al (2018). Efficacy of melatonin with behavioural sleep-wake scheduling for delayed sleep-wake phase disorder: A double-blind, randomised clinical trial. PLoS Medicine.
- 18
Erland LA, Saxena PK (2017). Melatonin Natural Health Products and Supplements: Presence of Serotonin and Significant Variability of Melatonin Content. Journal of Clinical Sleep Medicine.
- 19
Cohen PA, Avula B, Wang YH, Katragunta K, Khan I (2023). Quantity of Melatonin and CBD in Melatonin Gummies Sold in the US. JAMA.
- 20
American Academy of Sleep Medicine (2022). Melatonin use in children and adolescents: health advisory. American Academy of Sleep Medicine.
- 21
Lelak K, Vohra V, Neuman MI, Toce MS, Sethuraman U (2022). Pediatric Melatonin Ingestions - United States, 2012-2021. MMWR Morbidity and Mortality Weekly Report (CDC).
- 22
Freeman DI, Lind JN, Weidle NJ, Geller AI, Stone ND, Lovegrove MC (2024). Notes from the Field: Emergency Department Visits for Unsupervised Pediatric Melatonin Ingestion - United States, 2019-2022. MMWR Morbidity and Mortality Weekly Report (CDC).
- 23
National Center for Complementary and Integrative Health (NIH) (2024). Melatonin: What You Need To Know. NCCIH.
- 24
NHS (National Health Service, England) (2023). Melatonin: medicine information pages (about, who can and cannot take, other medicines, pregnancy and breastfeeding). NHS website (last reviewed 13 Feb 2023).
- 25
Therapeutic Goods Administration (Australia) (2021). Notice of final decision to amend the current Poisons Standard in relation to melatonin. TGA scheduling decisions (Schedule 3 entry effective 1 June 2021).
- 26
European Commission (2012). Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods (melatonin entries). Official Journal of the European Union.
- 27
ANSES (French Agency for Food, Environmental and Occupational Health & Safety) (2018). ANSES recommends that certain populations avoid the consumption of food supplements containing melatonin. ANSES.
- 28
Besag FMC, Vasey MJ, Lao KSJ, Wong ICK (2019). Adverse Events Associated with Melatonin for the Treatment of Primary or Secondary Sleep Disorders: A Systematic Review. CNS Drugs.
- 29
Otmani S, Demazières A, Staner C, et al (2008). Effects of prolonged-release melatonin, zolpidem, and their combination on psychomotor functions, memory recall, and driving skills in healthy middle aged and elderly volunteers. Human Psychopharmacology.
- 30
Mah J, Pitre T (2021). Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-Analysis. BMC Complementary Medicine and Therapies.
- 31
Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B (2012). The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. Journal of Research in Medical Sciences.
- 32
Arab A, Rafie N, Amani R, Shirani F (2023). The Role of Magnesium in Sleep Health: a Systematic Review of Available Literature. Biological Trace Element Research.
- 33
Lopresti AL, Smith SJ, Drummond PD (2026). Magnesium Supplementation for Sleep in Adults: A Systematic Review of Randomized Controlled Trials. Journal of Dietary Supplements.
- 34
Schuster J, Cycelskij I, Lopresti A, Hahn A (2025). Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial. Nature and Science of Sleep.
- 35
Hausenblas HA, Lynch T, Hooper S, Shrestha A, Rosendale D, Gu J (2024). Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial. Sleep Medicine: X.
- 36
Lopresti AL, Smith SJ (2026). The effects of magnesium L-threonate (Magtein) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial. Frontiers in Nutrition (vol 12, 2025; published Jan 2026).
- 37
NIH Office of Dietary Supplements (2026). Magnesium: Fact Sheet for Health Professionals (accessed 21 Oct 2026). National Institutes of Health.
- 38
Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, et al (2007). Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms.
- 39
Kawai N, Sakai N, Okuro M, et al (2015). The sleep-promoting and hypothermic effects of glycine are mediated by NMDA receptors in the suprachiasmatic nucleus. Neuropsychopharmacology.
- 40
Bulman A, D'Cunha NM, Marx W, Turner M, McKune A, Naumovski N (2025). The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis. Sleep Medicine Reviews.
- 41
Cotter J, Caddick CE, Harper JL, Ebajemito JK (2026). Examining the effect of L-theanine on sleep: a systematic review of dietary supplementation trials. Nutritional Neuroscience.
- 42
Fernández-San-Martín MI, Masa-Font R, Palacios-Soler L, Sancho-Gómez P, Calbó-Caldentey C, Flores-Mateo G (2010). Effectiveness of Valerian on insomnia: a meta-analysis of randomized placebo-controlled trials. Sleep Medicine.
- 43
Leach MJ, Page AT (2015). Herbal medicine for insomnia: A systematic review and meta-analysis. Sleep Medicine Reviews.
- 44
Shinjyo N, Waddell G, Green J (2020). Valerian Root in Treating Sleep Problems and Associated Disorders-A Systematic Review and Meta-Analysis. Journal of Evidence-Based Integrative Medicine.
- 45
Hieu TH, Dibas M, Surya Dila KA, et al (2019). Therapeutic efficacy and safety of chamomile for state anxiety, generalized anxiety disorder, insomnia, and sleep quality: A systematic review and meta-analysis of randomized trials and quasi-randomized trials. Phytotherapy Research.
- 46
National Center for Complementary and Integrative Health (NIH) (2024). Sleep Disorders and Complementary Health Approaches. NCCIH.
- 47
Möller HJ, Volz HP, Dienel A, Schläfke S, Kasper S (2019). Efficacy of Silexan in subthreshold anxiety: meta-analysis of randomised, placebo-controlled trials. European Archives of Psychiatry and Clinical Neuroscience.
- 48
Seifritz E, Kasper S, Möller HJ, et al (2022). Effect of anxiolytic drug silexan on sleep - a narrative review. World Journal of Biological Psychiatry.
- 49
Shen H, Zhang LJ, Zhu WY (2026). The Sleep-Enhancing Effect of Lavender Essential Oil in Adults: A Systematic Review and Meta-Analysis. Holistic Nursing Practice.
- 50
Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R (2021). Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis. PLoS One.
- 51
Björnsson HK, Björnsson ES, Avula B, et al (2020). Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver International.
- 52
Howatson G, Bell PG, Tallent J, Middleton B, McHugh MP, Ellis J (2012). Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality. European Journal of Nutrition.
- 53
Barforoush F, Ebrahimi S, Abdar MK, Khademi S, Morshedzadeh N (2025). The Effect of Tart Cherry on Sleep Quality and Sleep Disorders: A Systematic Review. Food Science & Nutrition.
- 54
Suraev AS, Marshall NS, Vandrey R, et al (2020). Cannabinoid therapies in the management of sleep disorders: A systematic review of preclinical and clinical studies. Sleep Medicine Reviews.
- 55
Narayan AJ, Downey LA, Rose S, Di Natale L, Hayley AC (2024). Cannabidiol for moderate-severe insomnia: a randomized controlled pilot trial of 150 mg of nightly dosing. Journal of Clinical Sleep Medicine.
- 56
Hepsomali P, Groeger JA, Nishihira J, Scholey A (2020). Effects of Oral Gamma-Aminobutyric Acid (GABA) Administration on Stress and Sleep in Humans: A Systematic Review. Frontiers in Neuroscience.
- 57
Richardson GS, Roehrs TA, Rosenthal L, Koshorek G, Roth T (2002). Tolerance to daytime sedative effects of H1 antihistamines. Journal of Clinical Psychopharmacology.
- 58
Morin CM, Koetter U, Bastien C, Ware JC, Wooten V (2005). Valerian-hops combination and diphenhydramine for treating insomnia: a randomized placebo-controlled clinical trial. Sleep.
- 59
2023 American Geriatrics Society Beers Criteria Update Expert Panel (2023). American Geriatrics Society 2023 updated AGS Beers Criteria for potentially inappropriate medication use in older adults. Journal of the American Geriatrics Society.
- 60
Gray SL, Anderson ML, Dublin S, et al (2015). Cumulative use of strong anticholinergics and incident dementia: a prospective cohort study. JAMA Internal Medicine.
- 61
Coupland CAC, Hill T, Dening T, Morriss R, Moore M, Hippisley-Cox J (2019). Anticholinergic Drug Exposure and the Risk of Dementia: A Nested Case-Control Study. JAMA Internal Medicine.
- 62
US Food and Drug Administration (2026). 21 CFR Part 338 - Nighttime sleep-aid drug products for over-the-counter human use (eCFR, accessed 21 Oct 2026). Electronic Code of Federal Regulations.