The peptide Epitalon (Epithalon; AEDG, Ala-Glu-Asp-Gly) has been studied for its effects on melatonin production and circadian rhythm regulation, particularly in models of ageing, but current evidence does not support Epitalon as a treatment for insomnia nor does it prove that it improves sleep quality, sleep duration, REM sleep, deep sleep or daytime functioning in humans. [1–6]
The link between Epitalon and sleep is biologically plausible, but often presented too broadly. Epitalon was developed as part of research into pineal peptides, and the pineal gland is the main source of melatonin, a hormone involved in signalling biological night and coordinating circadian rhythms. Therefore, experimental studies on Epitalon have analysed melatonin synthesis, pineal cell signalling, age-related changes in circadian rhythms, cortisol rhythms, and responses to abnormal lighting conditions. [1–6]
Available studies, however, measure mainly melatonin concentration or circadian endocrine markers, rather than sleep itself. This distinction is crucial. A substance may affect melatonin secretion without necessarily impacting insomnia, sleep efficiency, nocturnal awakenings, REM sleep, slow-wave sleep or the degree of restfulness the following day.
The most justifiable conclusion is that Epitalon exhibits a research signal related to the biology of the pineal gland and circadian rhythm, particularly in aging models, but direct clinical evidence regarding sleep improvement remains insufficient. [1–6]
Does Epitalon affect sleep?
Epitalon may indirectly influence biological processes related to sleep, as changes in melatonin production and circadian hormonal rhythms have been observed in experimental studies. However, a direct effect on sleep has not been adequately demonstrated in humans, and published studies do not confirm a reliable improvement in insomnia, sleep duration and efficiency, REM sleep, deep sleep, or subjective sleep quality. [1–6]
Much of the popular connection between Epitalon and sleep stems from research on melatonin.
Melatonin is produced mainly by the pineal gland during the biological night. Its secretion remains under the strict control of the circadian system and the light-dark cycle. Because Epitalon was developed as part of a research programme on pineal peptides and in several experiments affected parameters related to melatonin, it is sometimes referred to as a sleep peptide. [3–6]
However, such a description goes beyond the available evidence.
The most important Epitalon studies relating to this issue usually analysed one of four parameters: melatonin production by cultured pineal cells, melatonin secretion by isolated pineal glands, plasma melatonin rhythms in ageing rhesus macaques, or plasma melatonin patterns in elderly people. [1–6]
None of these parameters is equivalent to a comprehensive sleep study.
A modern clinical sleep trial typically evaluates parameters such as total sleep time, sleep latency, wake after sleep onset, sleep efficiency, nocturnal awakenings, REM sleep duration, slow-wave sleep, daytime sleepiness, insomnia severity, or patient-reported sleep quality. Depending on the research question, polysomnography, actigraphy, validated sleep questionnaires, or circadian phase markers may also be used.
Available evidence regarding Epitalon does not include a modern randomised human trial demonstrating an improvement in these parameters.
Therefore, Epitalon should not be described as a confirmed sleep aid solely because higher nocturnal melatonin levels were observed in some experiments.
A broader discussion of the involved biological pathways can be found in the article Mechanism of Action of Epitalon: How Does This Peptide Work?
Can Epitalon Affect Melatonin Production?
Yes, Epitalon affected biological processes related to melatonin in experimental studies: in rat pinealocyte culture it increased AANAT, pCREB and melatonin, and in studies of ageing rhesus macaques higher evening or night-time melatonin levels were observed. However, an experiment on the isolated rat pineal gland showed no effect on melatonin secretion, therefore the results are biologically interesting, but not fully consistent. [1–5]
The most direct mechanistic evidence comes from cultured rat pinealocytes.
Khavinson and co-workers studied Epithalon along with Vilon in rat pineal gland cells, measuring arylalkylamine N-acetyltransferase (AANAT) and phosphorylated CREB (pCREB). AANAT is an important enzyme in the melatonin synthesis pathway, whereas CREB-related transcription is involved in regulating the pineal gland's response to adrenergic signalling.
In this 2012 in vitro study on animal cells, Epithalon stimulated AANAT and pCREB synthesis and increased melatonin concentration in the culture medium. The addition of noradrenaline together with the peptides further enhanced AANAT and pCREB expression. [1]
This result provides a biologically plausible molecular link between Epitalon and melatonin synthesis.
A 2025 review of Epitalon additionally indicates that in this experiment on pinealocytes, the peptide exhibited a more prolonged effect than Vilon and remained particularly active at a later measurement point.
Another experiment, however, yielded different results.
Djeridane and co-workers studied isolated, perfused pineal glands of young and old male Wistar rats. AEDG was tested at concentrations ranging from 10^-6 to 10^-4 M. The researchers found no significant effect on basal melatonin secretion, regardless of the age of the animals. [2]
Pineal glands were also stimulated with isoproterenol, a beta-adrenergic receptor agonist, which normally increases melatonin secretion. Epitalon did not significantly alter this stimulated melatonin response either. [2]
Therefore, two related in vitro systems yielded contrasting results:
| Experimental model | Result | Level of evidence |
|---|---|---|
| Cultured rat pinealocytes | Increase in AANAT, pCREB and melatonin | In vitro evidence from animal cells [1] |
| Isolated pineal glands of young and old rats | No significant increase in basal melatonin secretion | In vitro evidence from the isolated organ [2] |
| Isolated pineal glands + isoprenaline | No significant modification of stimulated melatonin secretion | In vitro evidence from the isolated organ [2] |
| Ageing rhesus monkeys | Rise in evening/night-time melatonin levels | Evidence in non-human primates [3–5] |
| Observations in older people | Increase in nocturnal melatonin mainly in individuals with lower baseline pineal function | Limited evidence in humans [6] |
This inconsistency does not necessarily mean that either of the experiments was flawed. Cultured pinealocytes and the intact perfused pineal gland differ in cellular organisation, signalling environment, exposure conditions and feedback mechanisms.
However, this means that the statement „Epitalon always stimulates melatonin production” is not supported by the full body of available evidence.
What is the relationship between Epitalon and the pineal gland?
Epitalon is closely related to pineal gland research because the synthetic tetrapeptide AEDG was developed based on the amino acid composition of Epithalamin, a peptide preparation derived from the bovine pineal gland, and AEDG was later identified in the pineal polypeptide complex. Subsequently, experimental studies investigated whether Epitalon could modify age-related functions of the pineal gland and melatonin. [7]
The connection with the pineal gland is of both a historical and biological nature.
Before Epitalon was developed, researchers, including Vladimir Khavinson and Vladimir Anisimov, analysed Epithalamin, a peptide mixture derived from bovine pineal tissue. Epitalon was later synthesised as the specific sequence Ala-Glu-Asp-Gly (AEDG) based on research related to this preparation. [7]
A later analytical study identified AEDG among the peptides present in the pineal polypeptide complex, supporting the connection between the synthetic tetrapeptide and the initial pineal research programme. [7]
This story prompted scientists to investigate several issues related to the function of the pineal gland.
One of them was to determine whether Epitalon could modify melatonin synthesis. Another was to establish whether it could influence age-related changes in circadian hormonal rhythms. The morphology of the pineal gland, stress-related signalling, light-dependent effects of ageing and the links between pineal function and other hormonal systems were also investigated. [1–6]
The aspect related to ageing is of particular importance.
Several older experiments showed that old rhesus macaques had lower nighttime melatonin levels than young animals. Following the experimental administration of Epitalon, the nocturnal or evening melatonin concentration increased in the older animals. [3–5]
These results led researchers to describe Epitalon as a potential modulator of age-related pineal gland dysfunction rather than as a conventional sleeping pill or sedative.
This distinction matters.
It has not been shown that Epitalon acts like a direct melatonin supplement, benzodiazepines, orexin antagonists, sedative antihistamines, or other established sleep-affecting substances. The available literature suggests rather a possible regulation of biological systems affecting melatonin production.
More information on the origin and terminology of Epitalon can be found in the article What Is Epitalon Peptide? Definition, Names and Sequence.
Has Epitalon Been Studied for Circadian Rhythm Regulation?
Yes. Epitalon has been studied in the context of the circadian rhythm and chronobiological research, particularly in ageing rhesus macaques and in animal models subjected to abnormal lighting conditions. Several studies have observed changes in melatonin, cortisol or other circadian biological rhythms, but these results do not support the treatment of circadian rhythm sleep disorders in humans. [3–6,8]
The circadian rhythm is an approximately 24-hour biological cycle coordinated by the body's internal clocks and synchronised by environmental cues, primarily light.
Sleep remains heavily influenced by the circadian rhythm, but sleep and the circadian rhythm are not the same thing. The circadian system helps determine when the body is biologically prepared for sleep or wakefulness, whereas sleep itself also depends on mounting sleep pressure, behaviour, the environment, health status, medications and numerous neuronal systems.
Epitalon research on the circadian rhythm has focused primarily on hormonal rhythms.
In one study on non-human primates, Epithalon increased evening melatonin concentration in old female rhesus macaques and normalised certain aspects of the circadian cortisol secretion rhythm. [3]
A related study involving 38 female rhesus macaques included 18 younger monkeys aged 6–8 years and 20 older monkeys aged 20–26 years. The researchers observed a clear circadian rhythm of melatonin and analysed age-related disorders and responses to pineal peptide preparations, including Epitalon. [4]
Another study on old rhesus macaques showed lower nocturnal melatonin concentration associated with ageing and noted that administering Epitalon increased the baseline nocturnal melatonin concentration in older animals, whereas young animals did not show the same hormonal response. [5]
This age dependency is significant.
The evidence does not point to a simple, universal answer in which Epitalon unconditionally increases melatonin in every biological state. Instead, several researchers have interpreted its effect as normalising or regulatory, particularly under conditions of age-related reduced pineal gland function. [5,6]
Other rodent studies have analysed Epitalon under altered lighting cycles and experimental disruptions of neuroendocrine circadian rhythms. These studies support the chronobiological hypothesis, but still remain preclinical animal studies rather than proof that Epitalon treats jet lag, delayed sleep-wake phase disorder, shift work disorder or other clinical circadian rhythm disorders.
What Human Research Says About Sleep
Evidence from human studies does not show a direct benefit of Epitalon for sleep. The most relevant older study showed changes in nighttime melatonin levels and the circadian rhythm of melatonin in older adults, particularly those with reduced pineal gland function, but did not provide modern controlled evidence of improvements in insomnia, sleep architecture, sleep duration or quality. [6]
The most important publication concerning humans is the 2007 work by Korkushko and co-workers on pineal peptides in old monkeys and elderly people.
The authors described the age-related decrease in nocturnal and mean daily plasma melatonin concentrations, as well as a reduction in the amplitude of the circadian melatonin rhythm. They then demonstrated that the pineal peptide preparations Epithalamin and Epitalon restored the nocturnal concentration of endogenous melatonin and showed a tendency to normalise its circadian rhythm. [6]
In elderly individuals identified as having functional pineal insufficiency, the authors noted an increase in nocturnal melatonin concentration after treatment. [6]
This represents an interesting endocrine signal in humans, but several limitations prevent it from being considered strong evidence regarding the treatment of sleep disorders.
First, the abstract discusses both Epithalamin and Epitalon. These substances are historically linked, but are not chemically identical. Epithalamin is a complex pineal peptide preparation, whereas Epitalon is a defined AEDG tetrapeptide.
Secondly, the publication does not include in its abstract the level of methodological detail expected of a contemporary sleep study, including clearly described randomisation, placebo control, blinding, the number of participants assigned specifically to individual interventions, pre-defined sleep endpoints, and comprehensive monitoring of adverse events. [6]
Thirdly, the primary endpoint discussed is melatonin physiology, not clinical sleep.
The available study does not confirm changes in polysomnographic parameters such as sleep stages, REM latency, slow-wave sleep, arousal index, total sleep time or sleep efficiency.
The authors stated that no adverse events related to the preparations were observed in their study. [6] This historical observation should not be interpreted as evidence of general or long-term safety, as the available reporting method and sample characteristics do not allow for the assessment of rare or chronic adverse events.
There is therefore limited direct evidence in humans regarding changes in nocturnal melatonin levels, but insufficient clinical evidence regarding improvements in sleep.
Should Epitalon Be Taken in the Morning or Evening?
There is no evidence-based recommendation stating that Epitalon should be taken in the morning or evening to improve sleep, as no adequately controlled human study has established an optimal administration time, sleep-related dosing schedule, or chronotherapeutic protocol. Administration times used in animal studies and laboratory experiments cannot be safely translated into instructions for personal use.
This is an area where online advice often goes beyond the published evidence.
Intuitively, it might seem justified that a melatonin-related peptide should be administered in the evening. However, biological plausibility is not a dosage recommendation.
Available studies do not show that evening administration has a better effect on sleep in humans than morning administration.
It has also not been established that morning administration is more beneficial.
Literature regarding Epitalon covers very diverse experimental systems. In some studies, pineal cells were directly exposed to the peptide. [1] Other studies measured melatonin at various times of day in animals. [3–5] Still others analysed chronic administration under controlled light–dark cycle conditions.
These projects served to study biological mechanisms, rather than to compare morning and evening administration in the treatment of human insomnia.
Evening or night-time melatonin outcomes have also been reported in studies on non-human primates, but measuring an outcome at night does not mean that night-time is the optimal time for administering the test substance.
Therefore, statements such as „take Epitalon before bed”, „use it in the morning” or „night-time dosing is scientifically confirmed” are not supported by the analysed evidence.
The same restriction applies to the query „Epithalon dosage for sleep”. No clinically validated dose or administration schedule of Epitalon has been established for the treatment of insomnia, therefore experimental doses used in animals or concentrations used in cell cultures should not be translated into self-administration instructions.
Does Time Matter in Research Protocols?
Yes, time is of great importance in chronobiological research on Epitalon, because melatonin and other circadian hormones naturally change in concentration over 24 hours. Researchers therefore have to control light exposure, sampling time, age and baseline pineal function. However, the time requirements in research do not determine the optimal time for personal use of Epitalon.
Chronobiological research can easily lead to erroneous conclusions if the time of day is ignored.
Melatonin levels are typically low during the biological day and rise during the biological night. A blood sample taken in the afternoon therefore cannot be interpreted in the same way as a sample taken at night.
This problem was visible in studies on rhesus macaques.
W study involving 38 monkeys Plasma melatonin concentration showed a clear circadian rhythm, and the researchers compared younger and older animals, analysing the effect of pineal peptide preparations on this rhythm.
Other primate studies have specifically reported an increase evening or night melatonin concentrations after administration of Epitalon to older animals. [3,5]
Human studies have also focused on nocturnal melatonin, as the age-related deficit was most significant precisely during the period when its levels should physiologically be elevated. [6]
Lighting conditions also matter.
Animal studies have analysed Epitalon under standard light–dark cycles, continuous lighting, natural seasonal light rhythms and other modified photoperiods. These experiments are important because light exposure strongly influences pineal gland physiology and circadian rhythms.
Some studies on rats have shown that Epitalon differently modified biological parameters depending on lighting conditions, which reinforces the hypothesis that its experimental effects may be dependent on the biological state rather than fixed.
This has two consequences.
For researchers, the time of day and lighting conditions are key variables.
For consumers, these experiments they do not supply a validated protocol for morning or evening application.
Does Epitalon Cause Drowsiness?
There is no good evidence that Epitalon directly induces acute drowsiness or acts as a sedative. Research has focused primarily on melatonin production and circadian hormonal regulation rather than immediate subjective sleepiness. The increased nocturnal melatonin concentration observed in some experimental conditions should therefore not be interpreted as proof that Epitalon causes drowsiness.
Melatonin itself is best understood as circadian signal, and not simply as a sedative. Its physiological evening rise signals to tissues throughout the body the onset of the biological night.
An intervention affecting melatonin physiology could theoretically modify sleep timing without necessarily inducing immediate sedation.
Literature concerning Epitalon does not provide strong controlled human data showing that participants directly became drowsy, fell asleep quicker or exhibited measurable sedative effects upon administration.
A 2007 publication concerning human melatonin primarily describes endocrine changes. [6]
Animal studies also focus on melatonin, cortisol, pineal signalling or circadian rhythm markers, rather than behavioural sedation.
Therefore, the answer to the question „Does Epithalon cause drowsiness?” it is not a confirmed „yes”.
Is Epitalon a Treatment for Insomnia?
No. Epitalon has not been confirmed as an effective treatment for insomnia, and available peer-reviewed scientific studies do not include a modern randomised controlled trial in humans demonstrating an improvement in insomnia severity, sleep latency, nocturnal awakenings, sleep efficiency or total sleep time.
This distinction is particularly important because insomnia is a clinical disorder, not simply a state of low melatonin levels.
Insomnia can occur despite normal melatonin production and may be related, inter alia, to mental disorders, chronic pain, medications, sleep-related breathing disorders, restless legs syndrome, circadian rhythm desynchronisation, lifestyle and other causes.
Literature concerning Epitalon focuses primarily on the question of whether the peptide alters the biology of the pineal gland and circadian rhythm, particularly during ageing.
This is a scientifically different question to whether Epitalon cures insomnia.
Materials from the FDA Pharmacy Compounding Advisory Committee meeting in July 2026 indicate that insomnia was an evaluated use for reported bulk substances associated with Epitalon. Such an evaluation does not mean that the FDA has approved Epitalon for the treatment of insomnia. It means that the agency was considering bulk substances associated with Epitalon in the context of pharmacy compounding regulations.
The FDA separately indicates that it has not identified adequate compounding safety data for Epitalon for the proposed route of administration and notes potential concerns regarding immunogenicity, aggregation, peptide-related impurities and product characterisation.
Regulatory interest in the submission regarding insomnia should therefore not be interpreted as evidence that Epitalon is an approved or clinically validated treatment for insomnia.
Epitalon and Sleep – Summary of Evidence
The relationship between Epitalon and sleep is easier to interpret if the results regarding sleep are separated from the results regarding melatonin.
| Research question | What does the evidence show |
|---|---|
| Does Epitalon affect pathways related to melatonin? | Yes, in some experimental models. [1,3–6] |
| Does it increase AANAT and pCREB? | Yes, in cultured rat pinealocytes. [1] |
| Does it always increase the secretion of melatonin by the pineal gland? | No. The study of the isolated rat pineal gland showed no significant effect. [2] |
| Does it increase nighttime melatonin in old monkeys? | Such results have been described in several studies on non-human primates. [3–5] |
| Have changes in nocturnal melatonin been observed in older people? | Yes, in limited older studies, particularly in individuals with lower baseline pineal function. [6] |
| Does it experimentally restore hormonal rhythms? | There is evidence from animals and primates to suggest this. [3–6] |
| Does it improve sleep quality in humans? | Not determined. |
| Does it improve insomnia? | Not determined. |
| Does it increase REM sleep or deep sleep? | No direct evidence has been identified. |
| Does it reliably cause drowsiness? | Not determined. |
| Has the superiority of morning or evening administration been proven? | No. |
| Is there evidence-based dosing of Epitalon for sleep? | No validated clinical dosage has been established. |
Therefore, the overall picture of the evidence is much stronger with regard to melatonin and chronobiology than to treatment of sleep disorders.
Frequently Asked Questions about Epitalon and Sleep
Does Epitalon Help with Sleep?
Epitalon has not been shown to improve sleep in humans. Studies on animals, non-human primates and limited older studies in humans suggest that it may affect nocturnal melatonin levels and circadian hormonal regulation, particularly during ageing, but controlled evidence for improvements in sleep quality and duration, sleep latency or insomnia is lacking. [3–6]
Does Epitalon Increase Melatonin?
Epitalon increased melatonin in rat pinealocyte culture and evening or night-time melatonin levels in several studies on ageing rhesus macaques. Limited older human studies also showed higher nocturnal melatonin levels in older adults with reduced pineal gland function. However, a study of the isolated rat pineal gland showed no significant effect on melatonin, so the response is not universal across all models. [1–6]
Does Epitalon Cause Drowsiness?
There is no controlled evidence showing that Epitalon reliably causes acute somnolence. Published studies have mainly measured melatonin, cortisol, pineal signaling or circadian rhythms, rather than sedation or subjective sleepiness. Therefore, Epitalon's link to melatonin should not be interpreted as evidence of a sedative effect.
Is it better to take Epitalon in the morning or in the evening?
Neither morning nor evening administration was found to be superior in controlled human trials. Although many studies have measured night-time melatonin concentrations – as these physiologically peak during the biological night – the time of measurement is not the same as an evidence-based dosing schedule. Animal study protocols should not be interpreted as guidelines for personal use.
Is There an Epitalon Dosage for Sleep?
No validated dose of Epitalon for sleep or insomnia has been established in modern controlled human trials. Experimental doses and concentrations vary significantly between cell cultures, rodents, and non-human primates, and cannot be reliably converted into a human sleep protocol.
Does Epitalon Reset the Circadian Rhythm?
Epitalon modified endocrine patterns related to the circadian rhythm in animal and non-human primate studies, including melatonin and cortisol rhythms, and limited older human studies showed normalisation of nocturnal melatonin patterns. However, this does not confirm that Epitalon can clinically „reset” the circadian rhythm or treat jet lag, shift work disorder or delayed sleep-wake phase disorder. [3–6]
Does Epitalon Increase REM Phase or Deep Sleep?
There is no adequate evidence showing that Epitalon increases the REM phase or deep slow-wave sleep in humans. The available literature focuses primarily on melatonin secretion and circadian hormonal markers rather than sleep stages assessed polysomnographically.
How does Epitalon compare to DSIP in the context of sleep?
There are no appropriate direct head-to-head clinical trials showing whether Epitalon or delta sleep-inducing peptide (DSIP/emideltide) is more effective in the context of sleep. Their proposed biological mechanisms and research histories differ, and neither should be considered superior without controlled comparative studies involving humans.
Limitations of Evidence Regarding Epitalon and Sleep
The most important limitation is the discrepancy between what was actually measured and what is commonly stated.
Researchers measured melatonin.
In online discussions, better sleep is often talked about.
These are not equivalent results.
Human studies are also old and relatively limited, and their reporting is incomplete by modern clinical trial standards. Much of the mechanistic evidence, on the other hand, comes from rat pinealocytes, isolated rat pineal glands, ageing monkeys, and other preclinical models. [1–6]
Another significant limitation is the inconsistency of the results.
In an experiment on pinealocytes, an increase in melatonin-related signalling was observed, whereas an experiment on the isolated pineal gland showed no significant change in its secretion. [1,2] This contradiction argues against presenting Epitalon as a simple and direct melatonin stimulator.
Age may also modify the observed response. In several studies on primates, effects were observed mainly in older animals, whilst young animals showed little or no comparable hormonal response. [3–5]
The initial function of the pineal gland may also be of significance. In limited studies in older adults, a greater increase in nocturnal melatonin concentration was observed in individuals described as having a lower initial pineal function. [6]
This suggests that the interaction of the experimental compound Epitalon with the physiology of the circadian rhythm may be dependent on the biological state, although this hypothesis has not been adequately investigated in contemporary human studies.
Finally, there are no robust human data defining pharmacokinetics, the optimal time of administration in relation to sleep, the clinical dose-response relationship, the safety of chronic use, interactions with melatonin or hypnotics, or the long-term impact on the circadian system.
Disclaimer
This article is for educational and scientific-informational purposes only and does not constitute medical advice, diagnosis, therapeutic recommendations, dosing guidance, or a recommendation for the use of Epitalon. Epitalon/Epithalon (AEDG; Ala-Glu-Asp-Gly) is not approved by the FDA for the treatment of insomnia or the improvement of sleep; FDA documentation also indicates that the prior designation of Epitalon as an orphan drug in retinitis pigmentosa did not mean approval for that indication. The FDA currently indicates that compounded Epitalon may carry risks typical of peptides and that insufficient safety information has been identified for the evaluated proposed route of administration. The FDA also considered bulk substances related to Epitalon in the context of insomnia during the pharmacy compounding advisory process in July 2026, which is distinct from the approval of a substance as a medicinal product. Evidence regarding sleep remains primarily preclinical or based on limited older human endocrinological studies, rather than contemporary sleep research. The current status in the EU/EMA should similarly be verified in official European and national regulatory databases prior to clinical interpretation.
References
[1] Khavinson, V. K., Linkova, N. S., Kvetnoy, I. M., Kvetnaia, T. V., Polyakova, V. O., & Korf, H.-W. (2012). Molecular cellular mechanisms of peptide regulation of melatonin synthesis in pinealocyte culture. Bulletin of Experimental Biology and Medicine, 153(2), 255–258. https://doi.org/10.1007/s10517-012-1689-5
[2] Djeridane, Y., Khavinson, V. K., Anisimov, V. N., & Touitou, Y. (2003). Effect of a synthetic pineal tetrapeptide (Ala-Glu-Asp-Gly) on melatonin secretion by the pineal gland of young and old rats. Journal of Endocrinological Investigation, 26(3), 211–215. https://doi.org/10.1007/BF03345159
[3] Goncharova, N. D., Khavinson, V. K., & Lapin, B. A. (2001). Regulatory effect of Epithalon on production of melatonin and cortisol in old monkeys. Bulletin of Experimental Biology and Medicine, 131(4), 394–396. doi: 10.1023/A:1017928925177
[4] Khavinson, V., Goncharova, N., & Lapin, B. (2001). Synthetic tetrapeptide Epitalon restores disturbed neuroendocrine regulation in senescent monkeys. Neuro Endocrinology Letters, 22(4), 251–254. https://pubmed.ncbi.nlm.nih.gov/11524632/
[5] Goncharova, N. D., Vengerin, A. A., Khavinson, V. K., & Lapin, B. A. (2005). Pineal peptides restore the age-related disturbances in hormonal functions of the pineal gland and the pancreas. Experimental Gerontology, 40(1–2), 51–57. https://doi.org/10.1016/j.exger.2004.10.004
[6] Korkushko, O. V., Lapin, B. A., Goncharova, N. D., Khavinson, V. K., Shatilo, V. B., Vengerin, A. A., Antoniuk-Shcheglova, I. A., & Magdich, L. V. (2007). Normalising effect of the pineal gland peptides on the daily melatonin rhythm in old monkeys and elderly people. Advances in Gerontology, 20(1), 74–85. https://pubmed.ncbi.nlm.nih.gov/17969590/
[7] Araj, S. K., Brzezik, J., Mądra-Gackowska, K., & Szeleszczuk, Ł. (2025). Overview of Epitalon—Highly bioactive pineal tetrapeptide with promising properties. International Journal of Molecular Sciences, 26(6), 2691. https://doi.org/10.3390/ijms26062691