OnePin Peptide Library · Sleep
Melatonin
N-Acetyl-5-Methoxytryptamine
Melatonin (N-acetyl-5-methoxytryptamine) is a neurohormone primarily synthesized and secreted by the pineal gland in response to darkness. It is the master regulator of circadian rhythm, signaling nighttime to the body's internal clock (suprachiasmatic nucleus). Melatonin synthesis follows a clear diurnal pattern: levels begin rising 2-3 hours before habitual bedtime (dim light melatonin onset, or DLMO), peak in the middle of the night, and decline toward morning.,Melatonin acts through two G protein-coupled receptors: MT1 (promotes sleepiness and inhibits neuronal firing in the SCN) and MT2 (shifts circadian phase timing). Beyond sleep regulation, melatonin is a potent endogenous antioxidant with free radical scavenging properties, and it modulates immune function, body temperature, blood pressure, and reproductive hormone secretion. Endogenous melatonin production decreases with age, which may contribute to age-related sleep disturbances.,Melatonin is available over the counter in the United States as a dietary supplement, though it is a prescription medication in the European Union and many other countries. Research supports its use for circadian rhythm disorders (jet lag, delayed sleep phase syndrome, shift work disorder) and as a mild sleep aid. Notably, lower physiological doses (0.3-0.5mg) are often more effective than the high doses (5-10mg) commonly sold, as supraphysiological doses can desensitize receptors and cause morning grogginess.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Activates MT1 receptors in the suprachiasmatic nucleus (SCN) of the hypothalamus, directly promoting sleepiness by inhibiting wake-promoting neuronal firing. MT1 activation also suppresses cortisol and promotes the physiological transition to sleep.,Activates MT2 receptors in the SCN, which are primarily responsible for phase-shifting the circadian clock. This mechanism underlies melatonin's efficacy for jet lag and delayed sleep phase syndrome - it can advance or delay the circadian rhythm depending on timing of administration.,Functions as a direct free radical scavenger (neutralizing hydroxyl radicals and peroxynitrite) and indirect antioxidant by upregulating antioxidant enzymes (superoxide dismutase, glutathione peroxidase). Unlike most antioxidants, melatonin is amphiphilic and can cross all cellular membranes, including the blood-brain barrier and mitochondrial membranes.
Activates MT1 receptors in the suprachiasmatic nucleus (SCN) of the hypothalamus, directly promoting sleepiness by inhibiting wake-promoting neuronal firing. MT1 activation also suppresses cortisol and promotes the physiological transition to sleep.,Activates MT2 receptors in the SCN, which are primarily responsible for phase-shifting the circadian clock. This mechanism underlies melatonin's efficacy for jet lag and delayed sleep phase syndrome - it can advance or delay the circadian rhythm depending on timing of administration.,Functions as a direct free radical scavenger (neutralizing hydroxyl radicals and peroxynitrite) and indirect antioxidant by upregulating antioxidant enzymes (superoxide dismutase, glutathione peroxidase). Unlike most antioxidants, melatonin is amphiphilic and can cross all cellular membranes, including the blood-brain barrier and mitochondrial membranes.
What to expect
Days 1-3: Onset of sleepiness 30-60 minutes after dosing. Reduced time to fall asleep. If dose is too high, morning drowsiness may occur.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Safe & synergistic
Keep separate
Pharmacokinetics
Storage. Store at room temperature in a cool, dry place. Protect from light and moisture. Oral compound - no reconstitution needed.
Regulatory status
Available over the counter (OTC) as a dietary supplement in the United States. Prescription medication in the EU (Circadin 2mg prolonged-release), Australia, and many other countries. Not FDA-approved as a drug but generally recognized as safe (GRAS) at standard doses.
Put it to work
Calculate, log & track
Open Melatonin straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
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The guide & community
The complete Melatonin walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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