Melatonin

Watch our founder, Dr. Zak Zarbock, explain his philosophy about sleep.

Properties and mechanism of action

Naturally produced melatonin is a hormone, just like insulin or vitamin D—which means it is a signaling molecule released by the endocrine system. Once secreted by the pineal gland, melatonin binds to hormonal receptors throughout the body, including a part of the brain that regulates the body’s internal clock.³ 
Exogenous melatonin does not diminish the body’s ability to produce melatonin naturally.⁴ With a half-life of 35 to 50 minutes, exogenous melatonin reaches peak plasma concentrations after 60 minutes of administration, and 90% of it is cleared in a single passage through the liver.^5,6 A small amount is excreted in urine, and a small amount is found in saliva.⁶

Scientific support

Recent short- and long-term safety evaluations have demonstrated melatonin’s favorable safety profile for children.^7-11 Multiple studies have also shown that melatonin improves sleep onset latency and sleep duration among children and adults.^12-18*

^{*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.}

^{Ingredient details are provided as general information and are not intended to be associated with any specific Zarbee’s® products.}

^REFERENCES:

 ^{1. Ferracioli-Oda E, Qawasmi A, Bloch MH. Meta-analysis: melatonin for the treatment of primary sleep disorders. PLoS One. 2013;8(5):e63773. 2. Janjua I, Goldman RD. Sleep-related melatonin use in healthy children. Can Fam Physician. 2016;62(4):315-317. 3. Gobbi G, Comai S. Differential Function of Melatonin MT1 and MT2 Receptors in REM and NREM Sleep. Front Endocrinol (Lausanne). 2019;10:87. 4. Wright J, Aldhous M, Franey C, English J, Arendt J. The effects of exogenous melatonin on endocrine function in man. Clin Endocrinol (Oxf). 1986;24(4):375-382. 5. Melatonin. DrugBank. Accessed July 7, 2021.}

^{6. Tordjman S, Chokron S, Delorme R, et al. Melatonin: pharmacology, functions and therapeutic benefits. Curr Neuropharmacol. 2017;15(3):434-443. 7. McDonagh MS, Holmes R, Hsu F. Pharmacologic treatments for sleep disorders in children: a systematic review. J Child Neurol. 2019;34(5):237-247. 8. van Geijlswijk IM, Mol RH, Egberts TCG, Smits MG. Evaluation of sleep, puberty and mental health in children with long-term melatonin treatment for chronic idiopathic childhood sleep onset insomnia. Psychopharmacology (Berl). 2011;216(1):111-120. 9. Zwart TC, Smits MG, Egberts TCG, Rademaker CMA, van Geijlswijk IM. Long-term melatonin therapy for adolescents and young adults with chronic sleep onset insomnia and late melatonin onset: evaluation of sleep quality, chronotype, and lifestyle factors compared to age-related randomly selected population cohorts. Healthcare (Basel). 2018;6(1):23. 10. Boafo A, Greenham S, Alenezi S, et al. Could long-term administration of melatonin to prepubertal children affect timing of puberty? A clinician’s perspective. Nat Sci Sleep. 2019;11:1-10. 11. Malow BA, Findling RL, Schroder CM, et al. Sleep, growth, and puberty after 2 years of prolonged-release melatonin in children with Autism Spectrum Disorder. J Am Acad Child Adolesc Psychiatry. 2021;60(2):252-261.e3. 12. Eckerberg B, Lowden A, Nagai R, Åkerstedt T. Melatonin treatment effects on adolescent students’ sleep timing and sleepiness in a placebo-controlled crossover study. Chronobiol Int. 2012;29(9):1239-1248. 13. Ivanenko A, Crabtree VM, Tauman R, Gozal D. Melatonin in children and adolescents with insomnia: a retrospective study. Clin Pediatr (Phila). 2003;42(1):51-58. doi:10.1177/000992280304200108 14. Smits MG, Nagtegaal EE, van der Heijden J, Coenen AML, Kerkhof GA. Melatonin for chronic sleep onset insomnia in children: a randomized placebo-controlled trial. J Child Neurol. 2001;16(2):86-92. doi:10.1177/088307380101600204 15. Smits MG, van Stel HF, van der Heijden K, Meijer AM, Coenen AML, Kerkhof GA. Melatonin improves health status and sleep in children with idiopathic chronic sleep-onset insomnia: a randomized placebo-controlled trial. J Am Acad Child Adolesc Psychiatry. 2003;42(11):1286-1293. 16. van der Heijden KB, Smits MG, van Someren EJW, Boudewijn Gunning W. Prediction of melatonin efficacy by pretreatment dim light melatonin onset in children with idiopathic chronic sleep onset insomnia. J Sleep Res. 2005;14(2):187-194. doi:10.1111/j.1365-2869.2005.00451.x 17. van Maanen A, Meijer AM, Smits MG, van der Heijden KB, Oort FJ. Effects of melatonin and bright light treatment in childhood chronic sleep onset insomnia with late melatonin onset: a randomized controlled study. Sleep. 2017;40(2). doi:10.1093/sleep/zsw038 18. van Geijlswijk IM, van der Heijden KB, Egberts ACG, Korzilius HPLM, Smits MG. Dose finding of melatonin for chronic idiopathic childhood sleep onset insomnia: an RCT. Psychopharmacology (Berl). 2010;212(3):379-391. doi:10.1007/s00213-010-1962-0}