Melatonin
Also known as: Melatonin
Melatonin is the body's primary circadian hormone, secreted by the pineal gland to signal darkness and regulate sleep timing. It is widely studied as a chronobiotic and antioxidant research compound. Note: Melatonin is a small-molecule hormone, not a peptide, though it appears in some research-compound catalogs.
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Mechanism of Action
Melatonin is synthesized from serotonin via N-acetylation and O-methylation in pinealocytes, with secretion suppressed by light through retinohypothalamic input to the suprachiasmatic nucleus. It binds the G-protein-coupled MT1 and MT2 receptors, inhibiting cAMP and shifting circadian phase to promote sleep onset and entrainment. Beyond receptor signaling, melatonin acts as a direct free-radical scavenger and upregulates endogenous antioxidant enzymes. These combined chronobiotic and antioxidant actions underlie its research interest in sleep and aging.
- Half-life
- Approximately 20-50 minutes (immediate-release)
- Administration Routes
- oral
- Research Status
- Research Chemical
Reported Benefits
- Reduces sleep-onset latency in circadian and jet-lag research
- Helps entrain and phase-shift the circadian rhythm
- Acts as a direct and indirect antioxidant
- Studied for shift-work sleep disruption
- Generally well tolerated at low doses
- Investigated for immune and neuroprotective effects
Potential Side Effects
- Morning grogginess or drowsiness
- Vivid dreams or nightmares
- Headache and dizziness
- Possible mood changes at higher doses
Common Dosing
Research and clinical studies commonly use 0.5 mg to 5 mg taken 30-60 minutes before the target sleep time. Framed for research-use context only and not personal medical advice.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Caution with sedatives or CNS depressants
- Use care in those operating machinery due to drowsiness
- Potential interaction with anticoagulants
L-Glutathione
The body's principal intracellular antioxidant, a tripeptide with genuine human trial data behind oral and topical use -- and a 2025 systematic review concluding that the injectable route sold for skin lightening is contraindicated for lack of efficacy and side effects.
NAD+
NAD+ is an essential coenzyme central to cellular energy production and DNA repair whose levels decline with age. It is studied and supplemented for longevity, mitochondrial function, and metabolic health. Note: NAD+ is a coenzyme, not a peptide, commonly sold alongside longevity research compounds.
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The efficacy and safety of exogenous melatonin for primary sleep disorders. A meta-analysis
2005
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Melatonin as a Hormone: New Physiological and Clinical Insights
2018
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Meta-analysis: melatonin for the treatment of primary sleep disorders
2013
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Melatonin shifts human circadian rhythms according to a phase-response curve
1992
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Melatonin as an antioxidant: under promises but over delivers
2016