Moderate evidenceSleep & relaxation

Extended-Release Melatonin

A timed-release formulation designed to mimic the overnight melatonin curve rather than deliver one early spike. The best data are in adults over 55, where it modestly improves sleep quality and morning alertness; the effect sizes remain small.

Evidence last reviewed: August 2026

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What the science says

Sleep quality in adults aged 55 and over Moderate evidence
A randomised placebo-controlled trial in insomnia patients aged 55–80 found that 2 mg prolonged-release melatonin improved self-rated sleep quality and next-morning alertness. A later pooled analysis of the same programme confirmed that responses were consistent above roughly age 55 and less so below it.
Overall efficacy in insomnia disorder Moderate evidence
A systematic review and meta-analysis of melatonin and ramelteon in adult insomnia disorder found statistically significant but small improvements in sleep latency and sleep quality, with limited data on long-term outcomes. Extended-release forms were not clearly superior to immediate-release for falling asleep.
Staying asleep through the night Limited evidence
The rationale for the extended-release format is maintaining sleep rather than initiating it, but direct head-to-head trials against immediate-release melatonin on wake-after-sleep-onset are few and small. The advantage is theoretically sound but not firmly demonstrated.

Dosage & safety

Studied dose2 mg taken 1–2 hours before bedtime, the dose used in the prolonged-release trials. It is a prescription medicine in several countries and an over-the-counter supplement in others.

SafetyWell tolerated in trials up to 6–12 months, with headache and next-day sleepiness the most common effects. Do not crush or chew, as this destroys the release profile. Fluvoxamine and other CYP1A2 inhibitors, plus oral contraceptives, sharply raise melatonin blood levels; smoking lowers them. Caution with sedatives, anticoagulants and in autoimmune disease; discuss before use in pregnancy or breastfeeding.

Scientific references

Efficacy of prolonged release melatonin in insomnia patients aged 55-80 years: quality of sleep and next-day alertness outcomes
Wade AG, Ford I, Crawford G — Curr Med Res Opin, 2007
Prolonged release melatonin in the treatment of primary insomnia: evaluation of the age cut-off for short- and long-term response
Wade AG, Crawford G, Ford I — Curr Med Res Opin, 2011
Efficacy of melatonin and ramelteon for the acute and long-term management of insomnia disorder in adults: A systematic review and meta-analysis
Maruani J, Reynaud E, Chambe J — J Sleep Res, 2023

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