|This article relies on references to primary sources. (March 2012)|
|Systematic (IUPAC) name|
|Legal status||Prescription Only (S4) (AU) OTC (US)|
|Routes||In humans: orally, as capsules, tablets or liquid, sublingually, or as transdermal patches. In lab animals: also injection.|
|Bioavailability||30 – 50%|
|Metabolism||Hepatic via CYP1A2 mediated 6-hydroxylation|
|Half-life||35 to 50 minutes|
|Mol. mass||232.278 g/mol|
| (what is this?)
Melatonin i//, is also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes. In animals, circulating levels of the hormone melatonin vary in a daily cycle, thereby allowing the entrainment of the circadian rhythms of several biological functions.
Many biological effects of melatonin are produced through activation of melatonin receptors, while others are due to its role as a pervasive and powerful antioxidant, with a particular role in the protection of nuclear and mitochondrial DNA.
The full effects of long-term exogenous supplementation in humans have not yet been ascertained. Melatonin is categorized by the US Food and Drug Administration (FDA) as a dietary supplement, not a drug. A prescription-only, timed release melatonin product for people aged 55 and over was approved for use by the European Medicines Agency in 2007, despite having shown only small effects, and in Australia in 2009.
Melatonin has been identified in many plants including feverfew (Tanacetum parthenium), St John's wort (Hypericum perforatum)., rice, corn, tomato and edible fruits. The physiological roles of melatonin in plants involve regulation of their response to photoperiod, defense against harsh environments, and the function of an antioxidant. The latter may be the original function of melatonin in organisms with the others being added during evolution. Melatonin also regulates plant growth by its ability to slow root formation, while promoting above ground growth.
When birds ingest melatonin-rich plant feed, such as rice, the melatonin binds to melatonin receptors in their brains. When humans consume foods rich in melatonin such as banana, pineapple and orange the blood levels of melatonin significantly increase.
Many animals use the variation in duration of melatonin production each day as a seasonal clock. In animals including humans the profile of melatonin synthesis and secretion is affected by the variable duration of night in summer as compared to winter. The change in duration of secretion thus serves as a biological signal for the organisation of daylength-dependent (photoperiodic) seasonal functions such as reproduction, behaviour, coat growth and camouflage colouring in seasonal animals. In seasonal breeders that do not have long gestation periods and that mate during longer daylight hours, the melatonin signal controls the seasonal variation in their sexual physiology, and similar physiological effects can be induced by exogenous melatonin in animals including mynah birds and hamsters.
In mammals, melatonin is biosynthesized in four enzymatic steps from the essential dietary amino acid tryptophan, with serotonin produced at the second step. Melatonin is secreted into the blood by the pineal gland in the brain. Known as the "hormone of darkness," it is secreted in darkness in both day-active (diurnal) and night-active (nocturnal) animals. It may also be produced by a variety of peripheral cells such as bone marrow cells, lymphocytes, and epithelial cells. Usually, the melatonin concentration in these cells is much higher than that found in the blood, but it does not seem to be regulated by the photoperiod.
Melatonin can suppress libido by inhibiting secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the anterior pituitary gland, especially in mammals that have a breeding season when daylight hours are long. The reproduction of long-day breeders is repressed by melatonin and the reproduction of short-day breeders is stimulated by melatonin. During the night, melatonin regulates leptin, lowering its levels.
Light/dark information reaches the suprachiasmatic nuclei (SCN) from retinal photosensitive ganglion cells, which are intrinsically photosensitive photoreceptor cells that are distinct from those involved in the primary (at least, from one point of view) image formation function of the eye (that is the rods and cones of the retina). These cells represent approximately 2% of all retinal ganglion cells in humans and express the photopigment melanopsin.
Melanopsin, often confused with melatonin because of its similar name, is structurally unrelated to the hormone. It is a conventional 7-transmembrane opsin protein with the usual vitamin A-like cis-retinal cofactor having a peak absorption at 484 nm, in the blue light part of the visible spectrum. The photoperiod cue created by blue light (from a blue image of the sky) entrains a circadian rhythm, and thus governs resultant production of specific "dark"- and "light"-induced neural and endocrine signals that regulate behavioral and physiological circadian rhythms associated with melatonin. Melatonin is secreted in darkness in both day-active (diurnal) and night-active (nocturnal) animals.
In humans, melatonin is produced by the pineal gland, a small endocrine gland located in the center of the brain but outside the blood–brain barrier. The melatonin signal forms part of the system that regulates the sleep–wake cycle by chemically causing drowsiness and lowering the body temperature, but it is the central nervous system (specifically the suprachiasmatic nuclei, or SCN) that controls the daily cycle in most components of the paracrine and endocrine systems rather than the melatonin signal (as was once postulated).
Infants' melatonin levels become regular in about the third month after birth, with the highest levels measured between midnight and 08:00 (8 AM).
Human melatonin production decreases as a person ages. It is believed that as children become teenagers, the nightly schedule of melatonin release is delayed, leading to later sleeping and waking times.
It is principally blue light, around 460 to 480 nm, that suppresses melatonin, proportional to the light intensity and length of exposure. Until recent history, humans in temperate climates were exposed to few hours of (blue) daylight in the winter; their fires gave predominantly yellow light. The incandescent light bulb widely used in the twentieth century produced relatively little blue light. Wearing glasses that block blue light in the hours before bedtime may decrease melatonin loss. Kayumov et al. showed that light containing only wavelengths greater than 530 nm does not suppress melatonin in bright-light conditions. Use of blue-blocking goggles the last hours before bedtime has also been advised for people who need to adjust to an earlier bedtime, as melatonin promotes sleepiness.
When used several hours before sleep according to the phase response curve for melatonin in humans, small amounts (0.3 mg) of melatonin shift the circadian clock earlier, thus promoting earlier sleep onset and morning awakening.
Besides its function as synchronizer of the biological clock, melatonin was found to be a powerful free-radical scavenger and wide-spectrum antioxidant in 1993. In many less complex life forms, this is its only known function. Melatonin is an antioxidant that can easily cross cell membranes and the blood–brain barrier. This antioxidant is a direct scavenger of radical oxygen and nitrogen species including: OH, O2−, and NO. Melatonin works with other antioxidants to improve the overall effectiveness from each antioxidant.
While it is known that melatonin interacts with the immune system, the details of those interactions are unclear. There have been few trials designed to judge the effectiveness of melatonin in disease treatment. Most existing data are based on small, incomplete clinical trials. Any positive immunological effect is thought to be the result of melatonin acting on high-affinity receptors (MT1 and MT2) expressed in immunocompetent cells. In preclinical studies, melatonin may enhance cytokine production, and by doing this counteract acquired immunodeficiences. Some studies also suggest that melatonin might be useful fighting infectious disease including viral, such as HIV, and bacterial infections, and potentially in the treatment of cancer.
Endogenous melatonin in human lymphocytes has been related to interleukin-2 (IL-2) production and to the expression of IL-2 receptor. This suggests that melatonin is involved in the clonal expansion of antigen-stimulated human T lymphocytes. In rheumatoid arthritis patients, melatonin production has been found increased when compared to age-matched healthy controls.
Although it has not yet been clearly demonstrated whether melatonin increases non-specific immunity with resulting contraindication in autoimmune diseases, an increase in the production of IL-2 and IL-1 was noted in cultured splenocytes.
Some supplemental melatonin users report an increase in vivid dreaming. Extremely high doses of melatonin (50 mg) dramatically increased REM sleep time and dream activity in people both with and without narcolepsy. It has been suggested that nonpolar (lipid-soluble) indolic hallucinogenic drugs emulate melatonin activity in the awakened state and that both act on the same areas of the brain.
Some individuals with autism spectrum disorders (ASD) may have lower than normal levels of melatonin. A 2008 study found that unaffected parents of individuals with ASD also have lower melatonin levels, and that the deficits were associated with low activity of the ASMT gene, which encodes the last enzyme of melatonin synthesis.
Multiple small studies have demonstrated that 2 to 10 mg of melatonin may benefit children with ASD who have trouble falling asleep and/or maintaining sleep. A small 2011 randomized crossover trial found that the administration of melatonin, when compared to placebo, decreased sleep latency and increased total sleep time, but had no effect on the number of night time awakenings. At this time, no official guidelines exist for the use of melatonin in children with ASD.
Research has supported the anti-aging properties of melatonin. Younger children hit their peak melatonin production at night, and some researchers believe that the level of melatonin peaks earlier as people get older. This may explain why older adults go to bed earlier, wake up earlier, and have more sleep problems than children do.
Some studies have shown that melatonin plays a crucial part in the aging process and that it may act as an anti-aging agent when administered to older mice. It has been reported in one study that administration of melatonin in elderly mice may reverse this change in expression of some 13 genes, thus making them similar to those of younger mice. Consuming melatonin may neutralize oxidative damage and delay the neurodegenerative process of aging. When small amounts of melatonin were administered to lab mice, it reduced the oxidative damage caused by aging and delayed the inflammatory process, which in turn increased the longevity of the mice.
Single-nucleotide polymorphisms of the human melatonin MT2 receptor have been linked to an increased risk of developing type 2 diabetes. Furthermore women with low levels of melatonin secretion have been found to more likely to develop type 2 diabetes than women with high levels.
While the packaging of melatonin often warns against use in children, at least one long-term study does assess effectiveness and safety in children. No serious safety concerns were noted in any of the 94 cases studied by means of a structured questionnaire for the parents. With a mean follow-up time of 3.7 years, long-term medication was effective against sleep onset problems in 88% of the cases. Other studies warn against potential side effects
Melatonin has been studied as a potential treatment of gastroesophageal reflux disease, cancer, immune disorders, cardiovascular diseases, depression, seasonal affective disorder (SAD), circadian rhythm sleep disorders, sexual dysfunction and insomnia in the elderly. Prolonged release melatonin has shown good results in treating insomnia in older adults (2007). It may ameliorate circadian misalignment and SAD. Basic research indicates that melatonin may play a role in modulating the effects of drugs of abuse such as cocaine. Melatonin is also a geroprotector.
For many types of sleep disorders, melatonin is not effective. A 2006 review found that although it is safe for short term use (of three months or less), there is "no evidence that melatonin is effective in treating secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder."
In a 2005 study, researchers concluded that while "there is some evidence to suggest that melatonin is effective in treating delayed sleep phase syndrome(DSPS), ...there is evidence to suggest that melatonin is not effective in treating most primary sleep disorders with short-term use (4 weeks or less)."
Circadian rhythm disorders
Exogenous melatonin taken in the evening is, together with light therapy upon awakening, the standard treatment for delayed sleep phase syndrome (DSPS) and non-24-hour sleep-wake syndrome where circadian rhythms are not entrained to the environmental cycle. It appears to have some use against other circadian rhythm sleep disorders as well, such as jet lag and the problems of people who work rotating or night shifts. Melatonin reduces sleep onset latency to a greater extent in people with DSPS than in people with insomnia.
A very small dose taken several hours before bedtime in accordance with the phase response curve for melatonin in humans (PRC) doesn't cause sleepiness but, acting as a chronobiotic (affecting aspects of biological time structure), advances the phase slightly and is additive to the effect of using light therapy upon awakening. Light therapy may advance the phase about one to two-and-a-half hours and an oral dose of 0.3 or 3 mg of melatonin, timed correctly some hours before bedtime, can add about 30 minutes to the ~2 hour advance achieved with light therapy. There was no difference in the average magnitude of phase shift induced by the 2 doses.
Learning, memory and Alzheimer's
Melatonin receptors appear to be important in mechanisms of learning and memory in mice, and melatonin can alter electrophysiological processes associated with memory, such as long-term potentiation (LTP). The first published evidence that melatonin may be useful in Alzheimer's disease was the demonstration that this neurohormone prevents neuronal death caused by exposure to the amyloid beta protein, a neurotoxic substance that accumulates in the brains of patients with the disorder. Melatonin also inhibits the aggregation of the amyloid beta protein into neurotoxic microaggregates that, it seems, underlie the neurotoxicity of this protein, causing death of neurons and formation of neurofibrillary tangles, the other neuropathological landmark of Alzheimer's disease.
Melatonin has been shown to prevent the hyperphosphorylation of the tau protein in rats. Hyperphosphorylation of tau protein can also result in the formation of neurofibrillary tangles. Studies in rats suggest that melatonin may be effective for treating Alzheimer's disease. These same neurofibrillary tangles can be found in the hypothalamus in patients with Alzheimer's, adversely affecting their bodies' production of melatonin. Another study has implicated heightened afternoon agitation found in many Alzheimer's patients, called sundowning, with a phase delay in core body temperature. This may suggest a possible connection to melatonin production.
Research shows that after melatonin is administered to ADHD patients on methylphenidate, the time needed to fall asleep is significantly reduced. Furthermore, the effects of the melatonin after three months showed no change from its effects after one week of use.
Melatonin has been shown to be effective in treating seasonal affective disorder, a form of depression, and is being considered for bipolar and other disorders in which circadian disturbances are involved. It was observed in 1985 that bipolar disorder might have elevated sensitivity to light, i.e., a greater decrease in melatonin secretion in response to light exposure at night, as a "trait marker" (a characteristic of being bipolar, which does not change with state). This could be contrasted with drug-free recovered bipolar patients showing normal light sensitivity.
A systematic review of unblinded clinical trials involving a total of 643 cancer patients using melatonin found a reduced incidence of death but that blinded and independently conducted randomized controlled trials are needed. The National Cancer Institute's review of the evidence found that it remains inconclusive.
Melatonin presence in the gallbladder has many protective properties, such as converting cholesterol to bile, preventing oxidative stress, and increasing the mobility of gallstones from the gallbladder. It also decreases the amount of cholesterol produced in the gallbladder by regulating the cholesterol that passes through the intestinal wall. In guinea pigs, melatonin administration restored normal function by reducing inflammation after induced cholecystitis, whether administered before or after onset of inflammation. Concentration of melatonin in the bile is 2–3 times higher than the otherwise very low daytime melatonin levels in the blood across many diurnal mammals, including humans.
Amyotrophic lateral sclerosis
In animal models, melatonin has been shown to ameliorate glutamate-induced neuronal death, it is presumed due to its antioxidant effects. In a clinical safety study involving 31 ALS patients, high-dose rectal melatonin (300 mg/day for 2 years) was shown to be tolerated well.
Melatonin is involved in energy metabolism and body weight control in small animals. Many studies show that chronic melatonin supplementation in drinking water reduces body weight and abdominal fat in experimental animals, especially in the middle-aged rats and the weight loss effect did not require the animals to eat less and to be physically more active. A potential mechanism is that melatonin promotes the recruitment of brown adipose tissue (BAT) as well as enhances its activity. This effect would raise the basal metabolic rate by stimulating thermogenesis, heat generation through uncoupling oxidative phosphorylation in mitochondria. Whether the results of animal studies can be extrapolated to human obesity is a matter of future clinical trials, since substantially active BAT has been identified in adult humans.
Protection from radiation
Both animal and human studies have shown melatonin to be potentially radioprotective. Moreover, it is a more efficient protector than amifostine, a commonly used agent for this purpose. The mechanism of melatonin in protection against ionizing radiation is thought to involve scavenging of free radicals. It is estimated that nearly 70% of biological damage caused by ionizing radiation is attributable to the free radical, especially the hydroxyl radical that attacks DNA, proteins, and cellular membranes. Melatonin has been suggested as a radioprotective agent, with the proposed advantages of being broadly protective, readily available, orally self-administered, and without major known side effects.
Melatonin was used to treat periodic limb movement disorder, a common neurological condition, which, when severe, adversely affects sleep and causes excessive daytime fatigue, in a small trial conducted by Kunz D and Bes F. In this condition, the sufferer is affected by mini arousals during sleep and limb movements that occur in a frequent rhythmic fashion. This often involves leg kicking, but sometimes also involves arm movement. Those affected are often not aware of the condition, and partners are often the first to notice the condition. 7 out of the 9 participants in the trial showed significant improvement.
A research team in Italy has found that melatonin supplementation in the evening in perimenopausal women produces an improvement in thyroid function and gonadotropin levels, as well as restoring fertility and menstruation and preventing the depression associated with the menopause. One study reported that melatonin taken in the evening raised prolactin levels in six out of seven women.
Melatonin appears to cause very few side-effects in the short term, up to three months, when healthy people take it at low doses. A systematic review in 2006 looked specifically at efficacy and safety in two categories of melatonin usage: first, for sleep disturbances that are secondary to other diagnoses and, second, for sleep disorders such as jet lag and shift work that accompany sleep restriction.
The study concluded that "There is no evidence that melatonin is effective in treating secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder. There is evidence that melatonin is safe with short term use".
A similar analysis by the same team a year earlier on the efficacy and safety of exogenous melatonin in the management of primary sleep disorders found that: "There is evidence to suggest that melatonin is safe with short-term use (3 months or less)."
While no large, long-term studies that might reveal side-effects have been conducted, there do exist case reports about patients having taken melatonin for months.
Melatonin can cause somnolence (drowsiness), and, therefore, caution should be shown when driving, operating machinery, etc.
Individuals experiencing orthostatic intolerance, a cardiovascular condition that results in reduced blood pressure and blood flow to the brain when a person stands, may experience a worsening of symptoms when taking melatonin supplements, a study at Penn State College of Medicine's Milton S. Hershey Medical Center suggests. Melatonin can exacerbate symptoms by reducing nerve activity in those experiencing the condition, the study found.
Melatonin was thought to have a very low maternal toxicity in rats. Newer studies, though, have found that it is toxic to photoreceptor cells in rats' retinas and increases tumours in white mice.
Legal availability of melatonin varies in different countries, ranging from being available without prescription (e.g. in most of North America) to being available only on prescription or not at all (although its possession and use may not be illegal). In the UK it is available on prescription only.
The hormone may be administered orally, as capsules, tablets or liquid, sublingually, or as transdermal patches.
The use of melatonin derived from animal pineal tissue may carry the risk of contamination or the means of transmitting viral material. The synthetic form of this medication does not carry this risk.
In the USA, because it is sold as a dietary supplement, sometimes combined with other ingredients, such as vitamins and herbal extracts, and not as a drug, the Food and Drug Administration (FDA) regulations that apply to medications are not applicable to melatonin. However, new FDA rules required that by June 2010 all production of dietary supplements must comply with "current good manufacturing practices" (cGMP), and be manufactured with "controls that result in a consistent product free of contamination, with accurate labeling." In addition, the industry has been required to report to the FDA "all serious dietary supplement related adverse events" and the FDA has, within the cGMP guidelines, begun enforcement of that requirement.
As reported in the New York Times in May 2011, melatonin is sold in grocery stores, convenience stores, and clubs in both beverage and snack forms. The FDA is considering whether these food products can continue to be sold with the label "dietary supplements". On January 13, 2010, they issued a warning letter to Innovative Beverage, creators of several beverages marketed as "relaxation drinks," stating that melatonin is not approved as a food additive because it is not generally recognized as safe.
Melatonin is available as a prolonged-release prescription drug, trade-name Circadin, manufactured by Neurim Pharmaceuticals. The European Medicines Agency (EMA) has approved Circadin 2 mg (prolonged-release melatonin) for patients aged 55 or over, as monotherapy for the short-term treatment (up to 13 weeks) of primary insomnia characterized by poor quality of sleep.
Melatonin is related to the mechanism by which some amphibians and reptiles change the color of their skin and, indeed, it was in this connection the substance first was discovered. As early as 1917, Carey Pratt McCord and Floyd P. Allen discovered that feeding extract of the pineal glands of cows lightened tadpole skin by contracting the dark epidermal melanophores. In 1958 dermatology professor Aaron B. Lerner and colleagues at Yale University, in the hope that a substance from the pineal might be useful in treating skin diseases, isolated the hormone from bovine pineal gland extracts and named it melatonin. In the mid-70s Lynch et al. demonstrated that the production of melatonin exhibits a circadian rhythm in human pineal glands. The discovery that melatonin is an antioxidant was made in 1993. The first patent for its use as a low dose sleep aid was granted to Richard Wurtman at MIT in 1995. Around the same time, the hormone got a lot of press as a possible treatment for many illnesses. The New England Journal of Medicine editorialized in 2000: "The hype and the claims of the so-called miraculous powers of melatonin several years ago did a great disservice to a scientific field of real importance to human health. With these recent careful and precise observations in blind persons, the true potential of melatonin is becoming evident, and the importance of the timing of treatment is becoming clear. Our 24-hour society, with its chaotic time cues and lack of natural light, may yet reap substantial benefits."
|Wikimedia Commons has media related to: Melatonin|
- Discovery and development of melatonin receptor agonists
- Risks and benefits of sun exposure
- "Melatonin". Sleepdex. Retrieved 2011-08-17.
- Caniato R, Filippini R, Piovan A, Puricelli L, Borsarini A, Cappelletti EM (2003). "Melatonin in plants". Adv. Exp. Med. Biol. Advances in Experimental Medicine and Biology 527: 593–7. doi:10.1007/978-1-4615-0135-0_68. ISBN 978-0-306-47755-3. PMID 15206778.
- Paredes SD, Korkmaz A, Manchester LC, Tan DX, Reiter RJ (2009). "Phytomelatonin: a review". J. Exp. Bot. 60 (1): 57–69. doi:10.1093/jxb/ern284. PMID 19033551.
- Altun A, Ugur-Altun B (May 2007). "Melatonin: therapeutic and clinical utilization". Int. J. Clin. Pract. 61 (5): 835–45. doi:10.1111/j.1742-1241.2006.01191.x. PMID 17298593.
- Boutin JA, Audinot V, Ferry G, Delagrange P (August 2005). "Molecular tools to study melatonin pathways and actions". Trends Pharmacol. Sci. 26 (8): 412–9. doi:10.1016/j.tips.2005.06.006. PMID 15992934.
- Hardeland R (July 2005). "Antioxidative protection by melatonin: multiplicity of mechanisms from radical detoxification to radical avoidance". Endocrine 27 (2): 119–30. doi:10.1385/ENDO:27:2:119. PMID 16217125.
- Reiter RJ, Acuña-Castroviejo D, Tan DX, Burkhardt S (June 2001). "Free radical-mediated molecular damage. Mechanisms for the protective actions of melatonin in the central nervous system". Ann. N. Y. Acad. Sci. 939: 200–15. Bibcode:2001NYASA.939..200R. doi:10.1111/j.1749-6632.2001.tb03627.x. PMID 11462772.
- Ratzburg C (Undated). "Melatonin: The Myths and Facts". Vanderbilt University. Retrieved 2007-12-02.
- Buscemi N, Vandermeer B, Pandya R, Hooton N, Tjosvold L, Hartling L, Baker G, Vohra S, Klassen T (November 2004). "Melatonin for treatment of sleep disorders". Evidence Report/Technology Assessment No. 108. (Prepared by the University of Alberta Evidence-based Practice Center, under Contract No. 290-02-0023.) AHRQ Publication No. 05-E002-2. Rockville, MD: Agency for Healthcare Research and Quality. Agency for Healthcare Research and Quality (AHRQ), US Department of Health and Human Services. Retrieved 5 June 2013.
- European Medicines Agency. "Circadin, melatonin". European Public Assessment Report (EPAR). European Medicines Agency. Retrieved 5 June 2013.
- Therapeutic Goods Administration (TGA). "Australian Public Assessment Report for Melatonin". Department of Health and Ageing, Australian Government. Retrieved 5 June 2013.
- Tan DX, Hardeland R, Manchester LC, Korkmaz A, Ma S, Rosales-Corral S, Reiter RJ (January 2012). "Functional roles of melatonin in plants, and perspectives in nutritional and agricultural science". J. Exp. Bot. 63 (2): 577–97. doi:10.1093/jxb/err256. PMID 22016420.
- Tan DX, Hardeland R, Manchester LC, Paredes SD, Korkmaz A, Sainz RM, Mayo JC, Fuentes-Broto L, Reiter RJ (August 2010). "The changing biological roles of melatonin during evolution: from an antioxidant to signals of darkness, sexual selection and fitness". Biol Rev Camb Philos Soc 85 (3): 607–23. doi:10.1111/j.1469-185X.2009.00118.x. PMID 20039865.
- Arnao and Hernandez-Ruiz; Hernández-Ruiz, J (2006). "The Physiological Function of Melatonin in Plants". Plant Signaling & Behavior (Landes Bioscience) 1 (3): 89–95. doi:10.4161/psb.1.3.2640. PMC 2635004.
- Burkhardt S, Tan DX, Manchester LC, Hardeland R, Reiter RJ (October 2001). "Detection and quantification of the antioxidant melatonin in Montmorency and Balaton tart cherries (Prunus cerasus)". J. Agric. Food Chem. 49 (10): 4898–902. doi:10.1021/jf010321. PMID 11600041.
- Lamont KT, Somers S, Lacerda L, Opie LH, Lecour S (May 2011). "Is red wine a SAFE sip away from cardioprotection? Mechanisms involved in resveratrol- and melatonin-induced cardioprotection". J. Pineal Res. 50 (4): 374–80. doi:10.1111/j.1600-079X.2010.00853.x. PMID 21342247.
- Hattori A, Migitaka H, Iigo M, Itoh M, Yamamoto K, Ohtani-Kaneko R, Hara M, Suzuki T, Reiter RJ (March 1995). "Identification of melatonin in plants and its effects on plasma melatonin levels and binding to melatonin receptors in vertebrates". Biochem. Mol. Biol. Int. 35 (3): 627–34. PMID 7773197.
- Sae-Teaw M, Johns J, Johns NP, Subongkot S (October 2012). "Serum melatonin levels and antioxidant capacities after consumption of pineapple, orange, or banana by healthy male volunteers". J. Pineal Res.: n/a. doi:10.1111/jpi.12025. PMID 23137025.
- Lincoln GA, Andersson H, Loudon A (October 2003). "Clock genes in calendar cells as the basis of annual timekeeping in mammals--a unifying hypothesis". J. Endocrinol. 179 (1): 1–13. doi:10.1677/joe.0.1790001. PMID 14529560.
- Arendt J, Skene DJ (February 2005). "Melatonin as a chronobiotic". Sleep Med Rev 9 (1): 25–39. doi:10.1016/j.smrv.2004.05.002. PMID 15649736. "Exogenous melatonin has acute sleepiness-inducing and temperature-lowering effects during 'biological daytime', and when suitably timed (it is most effective around dusk and dawn) it will shift the phase of the human circadian clock (sleep, endogenous melatonin, core body temperature, cortisol) to earlier (advance phase shift) or later (delay phase shift) times."
- Chaturvedi CM (1984). "Effect of Melatonin on the Adrenl and Gonad of the Common Mynah Acridtheres tristis". Australian Journal of Zoology 32 (6): 803–9. doi:10.1071/ZO9840803.
- Chen HJ (July 1981). "Spontaneous and melatonin-induced testicular regression in male golden hamsters: augmented sensitivity of the old male to melatonin inhibition". Neuroendocrinology 33 (1): 43–6. doi:10.1159/000123198. PMID 7254478.
- Challet E (December 2007). "Minireview: Entrainment of the suprachiasmatic clockwork in diurnal and nocturnal mammals". Endocrinology 148 (12): 5648–55. doi:10.1210/en.2007-0804. PMID 17901231.
- Maestroni GJ (March 2001). "The immunotherapeutic potential of melatonin". Expert Opin Investig Drugs 10 (3): 467–76. doi:10.1517/135437188.8.131.527. PMID 11227046.
- Conti A, Conconi S, Hertens E, Skwarlo-Sonta K, Markowska M, Maestroni JM (May 2000). "Evidence for melatonin synthesis in mouse and human bone marrow cells". J. Pineal Res. 28 (4): 193–202. doi:10.1034/j.1600-079X.2000.280401.x. PMID 10831154.
- Kaur C, Ling EA (2008). "Antioxidants and neuroprotection in the adult and developing central nervous system". Curr. Med. Chem. 15 (29): 3068–80. doi:10.2174/092986708786848640. PMID 19075654.
- Nayak SK, Jegla T, Panda S (January 2007). "Role of a novel photopigment, melanopsin, in behavioral adaptation to light". Cell. Mol. Life Sci. 64 (2): 144–54. doi:10.1007/s00018-006-5581-1. PMID 17160354.
- Roberts JE (2005). "Update on the positive effects of light in humans". Photochem. Photobiol. 81 (3): 490–2. doi:10.1562/2004-12-02-IR-391. PMID 15656701.
- Reiter RJ (May 1991). "Pineal melatonin: cell biology of its synthesis and of its physiological interactions". Endocr. Rev. 12 (2): 151–80. doi:10.1210/edrv-12-2-151. PMID 1649044.
- Richardson GS (2005). "The human circadian system in normal and disordered sleep". J Clin Psychiatry. 66 Suppl 9: 3–9; quiz 42–3. PMID 16336035.
- Perreau-Lenz S, Pévet P, Buijs RM, Kalsbeek A (January 2004). "The biological clock: the bodyguard of temporal homeostasis". Chronobiol. Int. 21 (1): 1–25. doi:10.1081/CBI-120027984. PMID 15129821.
- Ardura J, Gutierrez R, Andres J, Agapito T (2003). "Emergence and evolution of the circadian rhythm of melatonin in children". Horm. Res. 59 (2): 66–72. doi:10.1159/000068571. PMID 12589109.
- Buscemi N, Vandermeer B, Pandya R, Hooton N, Tjosvold L, Hartling L, Baker G, Vohra S, Klassen T (November 2004). "Melatonin for treatment of sleep disorders". Evidence Report/Technology Assessment (Summary) (108): 1–7. PMID 15635761.
- Sack RL, Lewy AJ, Erb DL, Vollmer WM, Singer CM (1986). "Human melatonin production decreases with age". J. Pineal Res. 3 (4): 379–88. doi:10.1111/j.1600-079X.1986.tb00760.x. PMID 3783419.
- Gavin ML, Scaivina MT (2009). "Why Aren't Teens Getting Enough Sleep?". How Much Sleep Do I Need?.
- Brainard GC, Hanifin JP, Greeson JM, Byrne B, Glickman G, Gerner E, Rollag MD (August 2001). "Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor". J. Neurosci. 21 (16): 6405–12. PMID 11487664.
- Cornell University, Light source spectra
- Kayumov L, Casper RF, Hawa RJ, Perelman B, Chung SA, Sokalsky S, Shapiro CM (May 2005). "Blocking low-wavelength light prevents nocturnal melatonin suppression with no adverse effect on performance during simulated shift work". J. Clin. Endocrinol. Metab. 90 (5): 2755–61. doi:10.1210/jc.2004-2062. PMID 15713707.
- Burkhart K, Phelps JR. (26 December 2009). "Amber lenses to block blue light and improve sleep: a randomized trial". Retrieved 2012-07-09.
- Mundey K, Benloucif S, Harsanyi K, Dubocovich ML, Zee PC (October 2005). "Phase-dependent treatment of delayed sleep phase syndrome with melatonin". Sleep 28 (10): 1271–8. PMID 16295212.
- Terman MR, Wirz-Justice A (2009). Chronotherapeutics for Affective Disorders: A Clinician's Manual for Light and Wake Therapy. Basel: S Karger Pub. p. 71. ISBN 3-8055-9120-9.
- Poeggeler B, Reiter RJ, Tan DX, Chen LD, Manchester LC (May 1993). "Melatonin, hydroxyl radical-mediated oxidative damage, and aging: a hypothesis". J. Pineal Res. 14 (4): 151–68. PMID 8102180.
- Tan DX, Manchester LC, Terron MP, Flores LJ, Reiter RJ (January 2007). "One molecule, many derivatives: a never-ending interaction of melatonin with reactive oxygen and nitrogen species?". J. Pineal Res. 42 (1): 28–42. doi:10.1111/j.1600-079X.2006.00407.x. PMID 17198536.
- Pohanka M (2011). "Alzheimer´s disease and related neurodegenerative disorders: implication and counteracting of melatonin". Journal of Applied Biomedicine 9 (4): 185–196. doi:10.2478/v10136-011-0003-6.
- Reiter RJ, Manchester LC, Tan DX (September 2010). "Neurotoxins: free radical mechanisms and melatonin protection". Curr Neuropharmacol 8 (3): 194–210. doi:10.2174/157015910792246236. PMC 3001213. PMID 21358970.
- Poeggeler B, Saarela S, Reiter RJ, Tan DX, Chen LD, Manchester LC, Barlow-Walden LR (November 1994). "Melatonin--a highly potent endogenous radical scavenger and electron donor: new aspects of the oxidation chemistry of this indole accessed in vitro". Ann. N. Y. Acad. Sci. 738: 419–20. Bibcode:1994NYASA.738..419P. doi:10.1111/j.1749-6632.1994.tb21831.x. PMID 7832450.
- Carrillo-Vico A, Guerrero JM, Lardone PJ, Reiter RJ (July 2005). "A review of the multiple actions of melatonin on the immune system". Endocrine 27 (2): 189–200. doi:10.1385/ENDO:27:2:189. PMID 16217132.
- Arushanian EB, Beĭer EV (2002). "[Immunotropic properties of pineal melatonin]". Eksp Klin Farmakol (in Russian) 65 (5): 73–80. PMID 12596522.
- Carrillo-Vico A, Reiter RJ, Lardone PJ, Herrera JL, Fernández-Montesinos R, Guerrero JM, Pozo D (May 2006). "The modulatory role of melatonin on immune responsiveness". Curr Opin Investig Drugs 7 (5): 423–31. PMID 16729718.
- Maestroni GJ (1999). "Therapeutic potential of melatonin in immunodeficiency states, viral diseases, and cancer". Adv. Exp. Med. Biol. Advances in Experimental Medicine and Biology 467: 217–26. doi:10.1007/978-1-4615-4709-9_28. ISBN 978-1-4613-7133-5. PMID 10721059.
- Carrillo-Vico A, Lardone PJ, Fernández-Santos JM, Martín-Lacave I, Calvo JR, Karasek M, Guerrero JM (February 2005). "Human lymphocyte-synthesized melatonin is involved in the regulation of the interleukin-2/interleukin-2 receptor system". J. Clin. Endocrinol. Metab. 90 (2): 992–1000. doi:10.1210/jc.2004-1429. PMID 15562014.
- Cutolo M, Maestroni GJ (August 2005). "The melatonin-cytokine connection in rheumatoid arthritis". Ann. Rheum. Dis. 64 (8): 1109–11. doi:10.1136/ard.2005.038588. PMC 1755599. PMID 16014678.
- Arias J, Melean E, Valero N, Pons H, Chacín-Bonilla L, Larreal Y, Bonilla E (March 2003). "[Effect of melatonin on lymphocyte proliferation and production of interleukin-2 (IL-2) and interleukin-1 beta (IL-1 beta) in mice splenocytes]". Invest Clin (in Spanish; Castilian) 44 (1): 41–50. PMID 12703182.
- Lewis, Alan (1999). Melatonin and the Biological Clock. McGraw-Hill. p. 23. ISBN 0-87983-734-9.
- Virginia Hughes (November 13, 2011). "Genetic studies probe sleep hormones role in autism". Simons Foundation. Retrieved January 26, 2013.
- Melke J, Goubran Botros H, Chaste P, Betancur C, Nygren G, Anckarsäter H, Rastam M, Ståhlberg O, Gillberg IC, Delorme R, Chabane N, Mouren-Simeoni MC, Fauchereau F, Durand CM, Chevalier F, Drouot X, Collet C, Launay JM, Leboyer M, Gillberg C, Bourgeron T (January 2008). "Abnormal melatonin synthesis in autism spectrum disorders". Mol. Psychiatry 13 (1): 90–8. doi:10.1038/sj.mp.4002016. PMC 2199264. PMID 17505466.
- "Melatonin". MedlinePlus. December 24, 2011. Retrieved January 26, 2013.
- Wright B, Sims D, Smart S, Alwazeer A, Alderson-Day B, Allgar V, Whitton C, Tomlinson H, Bennett S, Jardine J, McCaffrey N, Leyland C, Jakeman C, Miles J (February 2011). "Melatonin versus placebo in children with autism spectrum conditions and severe sleep problems not amenable to behaviour management strategies: a randomised controlled crossover trial". J Autism Dev Disord 41 (2): 175–84. doi:10.1007/s10803-010-1036-5. PMID 20535539.
- Ehrlich SD (2012-01-20). "Melatonin". University of Maryland Medical Center.
- Sharman EH, Sharman KG, Ge YW, Lahiri DK, Bondy SC (April 2004). "Age-related changes in murine CNS mRNA gene expression are modulated by dietary melatonin". J. Pineal Res. 36 (3): 165–70. doi:10.1046/j.1600-079X.2003.00112.x. PMID 15009506.
- Acuña-Castroviejo D, Martín M, Macías M, Escames G, León J, Khaldy H, Reiter RJ (March 2001). "Melatonin, mitochondria, and cellular bioenergetics". J. Pineal Res. 30 (2): 65–74. doi:10.1034/j.1600-079X.2001.300201.x. PMID 11270481. Lay summary – Science Daily.
- Peschke E, Mühlbauer E (October 2010). "New evidence for a role of melatonin in glucose regulation". Best Pract. Res. Clin. Endocrinol. Metab. 24 (5): 829–41. doi:10.1016/j.beem.2010.09.001. PMID 21112029.
- McMullan CJ, Schernhammer ES, Rimm EB, Hu FB, Forman JP (April 2013). "Melatonin secretion and the incidence of type 2 diabetes". JAMA 309 (13): 1388–96. doi:10.1001/jama.2013.2710. PMID 23549584. Lay summary – ScienceDaily.
- Hoebert M, van der Heijden KB, van Geijlswijk IM, Smits MG (August 2009). "Long-term follow-up of melatonin treatment in children with ADHD and chronic sleep onset insomnia". J. Pineal Res. 47 (1): 1–7. doi:10.1111/j.1600-079X.2009.00681.x. PMID 19486273.
- Kandil TS, Mousa AA, El-Gendy AA, Abbas AM (January 2010). "The potential therapeutic effect of melatonin in Gastro-Esophageal Reflux Disease". BMC Gastroenterol 10: 7. doi:10.1186/1471-230X-10-7. PMC 2821302. PMID 20082715.
- Srinivasan V, Pandi-Perumal SR, Trahkt I, Spence DW, Poeggeler B, Hardeland R, Cardinali DP (2009). "Melatonin and melatonergic drugs on sleep: possible mechanisms of action". Int. J. Neurosci. 119 (6): 821–46. doi:10.1080/00207450802328607. PMID 19326288.
- Fornaro M, Prestia D, Colicchio S, Perugi G (September 2010). "A systematic, updated review on the antidepressant agomelatine focusing on its melatonergic modulation". Curr Neuropharmacol 8 (3): 287–304. doi:10.2174/157015910792246227. PMC 3001221. PMID 21358978.
- Turek FW, Gillette MU (November 2004). "Melatonin, sleep, and circadian rhythms: rationale for development of specific melatonin agonists". Sleep Med. 5 (6): 523–32. doi:10.1016/j.sleep.2004.07.009. PMID 15511698.
- Wade AG, Ford I, Crawford G, McMahon AD, Nir T, Laudon M, Zisapel N (October 2007). "Efficacy of prolonged release melatonin in insomnia patients aged 55-80 years: quality of sleep and next-day alertness outcomes". Curr Med Res Opin 23 (10): 2597–605. doi:10.1185/030079907X233098. PMID 17875243.
- Cassone VM (November 1990). "Effects of melatonin on vertebrate circadian systems". Trends Neurosci. 13 (11): 457–64. doi:10.1016/0166-2236(90)90099-V. PMID 1701579.
- Lewy AJ, Sack RL, Miller LS, Hoban TM (January 1987). "Antidepressant and circadian phase-shifting effects of light". Science 235 (4786): 352–4. Bibcode:1987Sci...235..352L. doi:10.1126/science.3798117. PMID 3798117.
- Sircar R (February 2000). "Effect of melatonin on cocaine-induced behavioral sensitization". Brain Res. 857 (1–2): 295–9. doi:10.1016/S0006-8993(99)02460-9. PMID 10700581.
- Uz T, Akhisaroglu M, Ahmed R, Manev H (December 2003). "The pineal gland is critical for circadian Period1 expression in the striatum and for circadian cocaine sensitization in mice". Neuropsychopharmacology 28 (12): 2117–23. doi:10.1038/sj.npp.1300254. PMID 12865893.
- Anisimov VN, Popovich IG, Zabezhinski MA, Anisimov SV, Vesnushkin GM, Vinogradova IA (2006). "Melatonin as antioxidant, geroprotector and anticarcinogen". Biochim. Biophys. Acta 1757 (5–6): 573–89. doi:10.1016/j.bbabio.2006.03.012. PMID 16678784.
- Buscemi N, Vandermeer B, Hooton N, Pandya R, Tjosvold L, Hartling L, Vohra S, Klassen TP, Baker G (February 2006). "Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis". BMJ 332 (7538): 385–93. doi:10.1136/bmj.38731.532766.F6. PMC 1370968. PMID 16473858.
- Buscemi N, Vandermeer B, Hooton N, Pandya R, Tjosvold L, Hartling L, Baker G, Klassen TP, Vohra S (December 2005). "The efficacy and safety of exogenous melatonin for primary sleep disorders. A meta-analysis". J Gen Intern Med 20 (12): 1151–8. doi:10.1111/j.1525-1497.2005.0243.x. PMC 1490287. PMID 16423108.
- H. W. Simpson (1979). "Chronobiotics: Selected Agents of Potential Value in Jet Lag and other Dyschronisms". In L.E. Sheving; F. Hagberg. Chronobiology: Principles and Application to Shifts in Schedules. Berlin: Springer. p. 433. ISBN 9789028609402. The reference discusses several chronobiotic substances, but not melatonin.
- Larson J, Jessen RE, Uz T, Arslan AD, Kurtuncu M, Imbesi M, Manev H (January 2006). "Impaired hippocampal long-term potentiation in melatonin MT2 receptor-deficient mice". Neurosci. Lett. 393 (1): 23–6. doi:10.1016/j.neulet.2005.09.040. PMID 16203090.
- Pappolla MA, Sos M, Omar RA, Bick RJ, Hickson-Bick DL, Reiter RJ, Efthimiopoulos S, Robakis NK (March 1997). "Melatonin prevents death of neuroblastoma cells exposed to the Alzheimer amyloid peptide". J. Neurosci. 17 (5): 1683–90. PMID 9030627.
- Pappolla M, Bozner P, Soto C, Shao H, Robakis NK, Zagorski M, Frangione B, Ghiso J (March 1998). "Inhibition of Alzheimer beta-fibrillogenesis by melatonin". J. Biol. Chem. 273 (13): 7185–8. doi:10.1074/jbc.273.13.7185. PMID 9516407.
- Wang XC, Zhang J, Yu X, Han L, Zhou ZT, Zhang Y, Wang JZ (February 2005). "Prevention of isoproterenol-induced tau hyperphosphorylation by melatonin in the rat". Sheng Li Xue Bao 57 (1): 7–12. PMID 15719129.
- Volicer L, Harper DG, Manning BC, Goldstein R, Satlin A (May 2001). "Sundowning and circadian rhythms in Alzheimer's disease". Am J Psychiatry 158 (5): 704–11. doi:10.1176/appi.ajp.158.5.704. PMID 11329390.
- Al-Aama T, Brymer C, Gutmanis I, Woolmore-Goodwin SM, Esbaugh J, Dasgupta M (July 2011). "Melatonin decreases delirium in elderly patients: a randomized, placebo-controlled trial". Int J Geriatr Psychiatry 26 (7): 687–94. doi:10.1002/gps.2582. PMID 20845391.
- Tjon Pian Gi CV, Broeren JP, Starreveld JS, Versteegh FG (July 2003). "Melatonin for treatment of sleeping disorders in children with attention deficit/hyperactivity disorder: a preliminary open label study". Eur. J. Pediatr. 162 (7–8): 554–5. doi:10.1007/s00431-003-1207-x. PMID 12783318.
- Dodick DW, Capobianco DJ (February 2001). "Treatment and management of cluster headache". Curr Pain Headache Rep 5 (1): 83–91. doi:10.1007/s11916-001-0015-0. PMID 11252143.
- Gagnier JJ (August 2001). "The therapeutic potential of melatonin in migraines and other headache types". Altern Med Rev 6 (4): 383–9. PMID 11578254.
- "Properly Timed Light, Melatonin Lift Winter Depression By Syncing Rhythms". National Institute of Mental Health. 2006-05-01. Retrieved 2011-08-17.
- Bhattacharjee Y (September 2007). "Psychiatric research. Is internal timing key to mental health?". Science 317 (5844): 1488–90. doi:10.1126/science.317.5844.1488. PMID 17872420.
- Lewy AJ, Nurnberger JI, Wehr TA, Pack D, Becker LE, Powell RL, Newsome DA (June 1985). "Supersensitivity to light: possible trait marker for manic-depressive illness". Am J Psychiatry 142 (6): 725–7. PMID 4003592.
- Whalley LJ, Perini T, Shering A, Bennie J (July 1991). "Melatonin response to bright light in recovered, drug-free, bipolar patients". Psychiatry Res 38 (1): 13–9. doi:10.1016/0165-1781(91)90048-T. PMID 1658841.
- Mills E, Wu P, Seely D, Guyatt G (November 2005). "Melatonin in the treatment of cancer: a systematic review of randomized controlled trials and meta-analysis". J. Pineal Res. 39 (4): 360–6. doi:10.1111/j.1600-079X.2005.00258.x. PMID 16207291.
- National Cancer Institute (May 2013). "Topics in complementary and alternative therapies (PDQ)". National Cancer Institute, National Institutes of Health. Retrieved 5 June 2013.
- Koppisetti S, Jenigiri B, Terron MP, Tengattini S, Tamura H, Flores LJ, Tan DX, Reiter RJ (October 2008). "Reactive oxygen species and the hypomotility of the gall bladder as targets for the treatment of gallstones with melatonin: a review". Dig. Dis. Sci. 53 (10): 2592–603. doi:10.1007/s10620-007-0195-5. PMID 18338264.
- Tan D, Manchester LC, Reiter RJ, Qi W, Hanes MA, Farley NJ (October 1999). "High physiological levels of melatonin in the bile of mammals". Life Sci. 65 (23): 2523–9. doi:10.1016/S0024-3205(99)00519-6. PMID 10622237.
- Weishaupt JH, Bartels C, Pölking E, Dietrich J, Rohde G, Poeggeler B, Mertens N, Sperling S, Bohn M, Hüther G, Schneider A, Bach A, Sirén AL, Hardeland R, Bähr M, Nave KA, Ehrenreich H (November 2006). "Reduced oxidative damage in ALS by high-dose enteral melatonin treatment". J. Pineal Res. 41 (4): 313–23. doi:10.1111/j.1600-079X.2006.00377.x. PMID 17014688.
- Wolden-Hanson T, Mitton DR, McCants RL, Yellon SM, Wilkinson CW, Matsumoto AM, Rasmussen DD (February 2000). "Daily melatonin administration to middle-aged male rats suppresses body weight, intraabdominal adiposity, and plasma leptin and insulin independent of food intake and total body fat". Endocrinology 141 (2): 487–97. doi:10.1210/en.141.2.487. PMID 10650927.
- Tan DX, Manchester LC, Fuentes-Broto L, Paredes SD, Reiter RJ (March 2011). "Significance and application of melatonin in the regulation of brown adipose tissue metabolism: relation to human obesity". Obes Rev 12 (3): 167–88. doi:10.1111/j.1467-789X.2010.00756.x. PMID 20557470.
- Vijayalaxmi, Meltz ML, Reiter RJ, Herman TS, Kumar KS (March 1999). "Melatonin and protection from whole-body irradiation: survival studies in mice". Mutat. Res. 425 (1): 21–7. doi:10.1016/S0027-5107(98)00246-2. PMID 10082913.
- Vijayalaxmi, Reiter RJ, Herman TS, Meltz ML (December 1996). "Melatonin and radioprotection from genetic damage: in vivo/in vitro studies with human volunteers". Mutat. Res. 371 (3–4): 221–8. doi:10.1016/S0165-1218(96)90110-X. PMID 9008723.
- Vijayalaxmi, Reiter RJ, Herman TS, Meltz ML (February 1998). "Melatonin reduces gamma radiation-induced primary DNA damage in human blood lymphocytes". Mutat. Res. 397 (2): 203–8. doi:10.1016/S0027-5107(97)00211-X. PMID 9541644.
- Topkan E, Tufan H, Yavuz AA, Bacanli D, Onal C, Kosdak S, Yavuz MN (October 2008). "Comparison of the protective effects of melatonin and amifostine on radiation-induced epiphyseal injury". Int. J. Radiat. Biol. 84 (10): 796–802. doi:10.1080/09553000802389678. PMID 18979313.
- Shirazi A, Ghobadi G, Ghazi-Khansari M (July 2007). "A radiobiological review on melatonin: a novel radioprotector". J. Radiat. Res. 48 (4): 263–72. doi:10.1269/jrr.06070. PMID 17641465.
- Hurtuk A, Dome C, Holloman CH, Wolfe K, Welling DB, Dodson EE, Jacob A (July 2011). "Melatonin: can it stop the ringing?". Ann. Otol. Rhinol. Laryngol. 120 (7): 433–40. PMID 21859051.
- Megwalu UC, Finnell JE, Piccirillo JF (February 2006). "The effects of melatonin on tinnitus and sleep". Otolaryngol Head Neck Surg 134 (2): 210–3. doi:10.1016/j.otohns.2005.10.007. PMID 16455366.
- Rosenberg SI, Silverstein H, Rowan PT, Olds MJ (March 1998). "Effect of melatonin on tinnitus". Laryngoscope 108 (3): 305–10. doi:10.1097/00005537-199803000-00001. PMID 9504599.
- Pirodda A, Raimondi MC, Ferri GG (August 2010). "Exploring the reasons why melatonin can improve tinnitus". Med. Hypotheses 75 (2): 190–1. doi:10.1016/j.mehy.2010.02.018. PMID 20207491.
- Kunz D, Bes F (March 2001). "Exogenous melatonin in periodic limb movement disorder: an open clinical trial and a hypothesis". Sleep 24 (2): 183–7. PMID 11247054.
- Basu PP, Pacana T, Shah N, Hampole H, Krishnaswamy N, Rayapudi K (2010). "Role of melatonin in colonic motility in irritable bowel syndrome - Constipation MIMI-C-a double blinded randomized placebocontrol clinical trial". Neurogastroenterology & Motility 22: 23–90. doi:10.1111/j.1365-2982.2010.01549.x.
- Bellipanni G, DI Marzo F, Blasi F, Di Marzo A (December 2005). "Effects of melatonin in perimenopausal and menopausal women: our personal experience". Ann. N. Y. Acad. Sci. 1057: 393–402. Bibcode:2005NYASA1057..393B. doi:10.1196/annals.1356.030. PMID 16399909.
- Terzolo M, Revelli A, Guidetti D, Piovesan A, Cassoni P, Paccotti P, Angeli A, Massobrio M (August 1993). "Evening administration of melatonin enhances the pulsatile secretion of prolactin but not of LH and TSH in normally cycling women". Clin. Endocrinol. (Oxf) 39 (2): 185–91. doi:10.1111/j.1365-2265.1993.tb01772.x. PMID 8370131.
- Brent Bauer, M.D. "Melatonin side effects: What are the risks?". Mayo Clinic. Retrieved 2011-08-17.
- Zhdanova IV, Wurtman RJ, Regan MM, Taylor JA, Shi JP, Leclair OU (October 2001). "Melatonin treatment for age-related insomnia". J. Clin. Endocrinol. Metab. 86 (10): 4727–30. doi:10.1210/jc.86.10.4727. PMID 11600532.
- Sack RL, Brandes RW, Kendall AR, Lewy AJ (October 2000). "Entrainment of free-running circadian rhythms by melatonin in blind people". N. Engl. J. Med. 343 (15): 1070–7. doi:10.1056/NEJM200010123431503. PMID 11027741.
- Morera AL, Henry M, de La Varga M (2001). "[Safety in melatonin use]". Actas Esp Psiquiatr (in Spanish; Castilian) 29 (5): 334–7. PMID 11602091.
- Terry PD, Villinger F, Bubenik GA, Sitaraman SV (January 2009). "Melatonin and ulcerative colitis: evidence, biological mechanisms, and future research". Inflamm. Bowel Dis. 15 (1): 134–40. doi:10.1002/ibd.20527. PMID 18626968.
- "Study Shows Melatonin Supplements May Make Standing A Hazard For The Cardiovascular-Challenged" (DOC) (Press release). Penn State College of Medicine, Milton S. Hershey Medical Center. September 2003. Retrieved 2006-07-21. (MS Word Format)
- Juszczak M, Michalska M (2006). "[The effect of melatonin on prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) synthesis and secretion]". Postepy Hig Med Dosw (Online) (in Polish) 60: 431–8. PMID 16921343.
- Srinivasan V, Spence WD, Pandi-Perumal SR, Zakharia R, Bhatnagar KP, Brzezinski A (December 2009). "Melatonin and human reproduction: shedding light on the darkness hormone". Gynecol. Endocrinol. 25 (12): 779–85. doi:10.3109/09513590903159649. PMID 19905996.
- Cohen M, van Heusden AM, Verdonk HER, Wijnhamer P: Melatonin/Norethisterone contraception. In Melatonin and the Pineal Gland- From Basic Science to Clinical Application. Edited by Touitou Y, Arendt J and Pevet P. Amsterdam, Elsevier Science Publishers; 1993:339-345.
- Jahnke G, Marr M, Myers C, Wilson R, Travlos G, Price C (August 1999). "Maternal and developmental toxicity evaluation of melatonin administered orally to pregnant Sprague-Dawley rats". Toxicol. Sci. 50 (2): 271–9. doi:10.1093/toxsci/50.2.271. PMID 10478864.
- Wiechmann AF, Chignell CF, Roberts JE (February 2008). "Influence of dietary melatonin on photoreceptor survival in the rat retina: an ocular toxicity study". Exp. Eye Res. 86 (2): 241–50. doi:10.1016/j.exer.2007.10.015. PMC 2377032. PMID 18078931.
- Anisimov VN, Zavarzina NY, Zabezhinski MA, Popovich IG, Zimina OA, Shtylick AV, Arutjunyan AV, Oparina TI, Prokopenko VM, Mikhalski AI, Yashin AI (July 2001). "Melatonin increases both life span and tumor incidence in female CBA mice". J. Gerontol. A Biol. Sci. Med. Sci. 56 (7): B311–23. doi:10.1093/gerona/56.7.B311. PMID 11445596.
- Rodriguez RR (January 13, 2010). "Warning Letter". Inspections, Compliance, Enforcement, and Criminal Investigations. U.S. Food and Drug Administration.
- "Melatonin". Drugs.com. Retrieved 2011-08-17.
- "FDA Issues Dietary Supplements Final Rule" (Press release). U.S. Food and Drug Administration. 2007-06-22. Retrieved 2009-08-04.
- Catherine Saint Louis (14 May 2011). "Dessert, Laid-Back and Legal". New York Times.
- Medical News Today Circadin (Prolonged-Release Melatonin) For Primary Insomnia Recommended For Approval In The EU (27 Apr 2007)
- Filadelfi AM, Castrucci AM (May 1996). "Comparative aspects of the pineal/melatonin system of poikilothermic vertebrates". J. Pineal Res. 20 (4): 175–86. doi:10.1111/j.1600-079X.1996.tb00256.x. PMID 8836950.
- Sugden D, Davidson K, Hough KA, Teh MT (October 2004). "Melatonin, melatonin receptors and melanophores: a moving story". Pigment Cell Res. 17 (5): 454–60. doi:10.1111/j.1600-0749.2004.00185.x. PMID 15357831.
- Coates PM, Blackman MR, Cragg GM, LevineM, Moss J, White JD (2005). Encyclopedia of dietary supplements. New York, N.Y: Marcel Dekker. pp. 457–466. ISBN 0-8247-5504-9.
- McCord CP, Allen FP (January 1917). "Evidences associating pineal gland function with alterations in pigmentation". J Exptl Zool 23 (1): 206–224.
- Lerner AB, Case JD, Takahashi Y (July 1960). "Isolation of melatonin and 5-methoxyindole-3-acetic acid from bovine pineal glands". J. Biol. Chem. 235: 1992–7. PMID 14415935.
- Lynch HJ, Wurtman RJ, Moskowitz MA, Archer MC, Ho MH (January 1975). "Daily rhythm in human urinary melatonin". Science 187 (4172): 169–71. Bibcode:1975Sci...187..169L. doi:10.1126/science.1167425. PMID 1167425.
- Poeggeler B, Reiter RJ, Tan DX, Chen LD, Manchester LC (May 1993). "Melatonin, hydroxyl radical-mediated oxidative damage, and aging: a hypothesis". J. Pineal Res. 14 (4): 151–68. doi:10.1111/j.1600-079X.1993.tb00498.x. PMID 8102180.
- US patent 5449683, Wurtman RJ, "Methods of inducing sleep using melatonin", issued 1995-09-12, assigned to Massachusetts Institute of Technology
- Arendt J (August 2005). "Melatonin: characteristics, concerns, and prospects". J. Biol. Rhythms 20 (4): 291–303. doi:10.1177/0748730405277492. PMID 16077149. "There is very little evidence in the short term for toxicity or undesirable effects in humans. The extraordinary “hype” of the miraculous powers of melatonin in the recent past did a disservice to acceptance of its genuine benefits."
- Arendt J (October 2000). "Melatonin, circadian rhythms, and sleep". N. Engl. J. Med. 343 (15): 1114–6. doi:10.1056/NEJM200010123431510. PMID 11027748.
- Wade AG, Ford I, Crawford G, McConnachie A, Nir T, Laudon M, Zisapel N (2010). "Nightly treatment of primary insomnia with prolonged release melatonin for 6 months: a randomized placebo controlled trial on age and endogenous melatonin as predictors of efficacy and safety". BMC Med 8: 51. doi:10.1186/1741-7015-8-51. PMC 2933606. PMID 20712869.