Dosage guide
Melatonin dosage
Melatonin dosing: typical range, frequency, half-life, onset, routes. Evidence-tiered.
At a glance
- Typical dose
- 0.5mg
- Half-life
- 0.75hr
- Frequency
- daily, 30 to 60 minutes before target sleep time
- Routes
- oral, sublingual
Protocol
- 1
Measure the dose
Typical Melatonin dose is 0.5 mg. Use a weight-based calculator for individual adjustments.
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Set the frequency
Administer daily, 30 to 60 minutes before target sleep time. Half-life of 0.75 hours anchors the dosing interval.
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Cycle if needed
No formal cycling required; many users take only as needed for jet lag or shift work
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Monitor for side effects
Watch for: vivid dreams; morning grogginess (higher doses); headache; dizziness. Stop or reduce dose if tolerability breaks down.
Why this dose
Agonist at MT1 and MT2 receptors in the suprachiasmatic nucleus, signaling biological night and promoting sleep-onset gating plus circadian phase shifts.
The typical 0.5 mg dose is the figure most commonly used in published protocols for Melatonin. Treat the label as a starting point: body weight, training status, sleep, diet, and concurrent medications all shift the effective dose-response curve in real users.
How to administer
Melatonin is administered via the oral or sublingual routes. Oral dosing is straightforward: take with water, with or without food unless specifically noted. Sublingual dosing requires holding the dose under the tongue for 60 to 90 seconds before swallowing to maximize mucosal absorption.
Onset of action runs around 30 minutes after administration. Peak effect lands near 1 hour post-dose. Plan the administration window so that peak effect lines up with whatever outcome you are dosing for, whether that is training, sleep, or symptom coverage.
Half-life note: Immediate-release ~30 to 50 minutes; extended-release formulations ~3.5 to 4 hours
Cycling and tolerance
No formal cycling required; many users take only as needed for jet lag or shift work
Effects to expect at typical dose
- Shortens sleep onset latency by ~7 to 12 minutes at physiological 0.3 to 1 mg doses
- Advances circadian phase when taken 30 to 60 minutes before target bedtime, useful for jet lag and shift work
- Does not meaningfully increase total sleep time in healthy adults without circadian misalignment
- Endogenous nighttime production is not suppressed by short-term exogenous supplementation
- Higher doses (3 to 10 mg) raise plasma levels above physiological range and often increase morning grogginess
- Effective for delayed sleep-wake phase disorder and reducing jet-lag severity in eastward travel
Best-graded outcomes
- A Sleep onset latency : 7 to 12 minute reduction at low doses (Adults at 0.3 to 1 mg).
- A Circadian phase advance (jet lag) : Robust reductions in jet-lag severity (Eastward travel, shift work).
- A Sleep onset in pediatric ASD : Robust onset latency reductions; Cochrane support (Children with autism spectrum disorder).
Side effects and interactions
Common side effects
- vivid dreams
- morning grogginess (higher doses)
- headache
- dizziness
Notable interactions
- fluvoxamine (major): CYP1A2 inhibition raises melatonin levels substantially
- warfarin (moderate): possible increased bleeding risk
- benzodiazepines and alcohol (moderate): additive sedation
- antihypertensives (minor): may alter blood pressure response
Lists above cover commonly reported and well-characterized items. They are not exhaustive: review the full Melatonin profile and discuss with a clinician familiar with your medication list before starting, particularly if you are on prescription therapy or have a chronic condition.
Regulatory snapshot
- WADA status
- allowed
- DEA / Rx
- OTC supplement in US; Rx in UK, EU, Japan, Australia
- Pregnancy
- Insufficient data; not routinely recommended
- Legal status
- OTC in US; prescription in UK, EU, Japan
Do not use if
- autoimmune disease (theoretical)
- concurrent anticoagulant therapy without monitoring
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