How long does it take for melatonin to work
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How Long Does It Take for Melatonin to Work?
Melatonin, a hormone produced by the pineal gland, is widely used to treat various sleep disorders. Understanding how quickly melatonin takes effect can help optimize its use for better sleep outcomes.
Melatonin Onset Time in Different Populations
General Population and Healthy Individuals
In healthy young adults, melatonin can significantly reduce sleep onset latency when taken 2-4 hours before habitual bedtime. A study involving 12 young volunteers showed that both 0.3 mg and 1.0 mg doses of melatonin decreased the time it took to fall asleep without altering sleep architecture or causing morning hangover effects . This suggests that melatonin can start working within a couple of hours in healthy individuals.
Children with Neurodevelopmental Disorders
For children with neurodevelopmental disorders, melatonin also shows a rapid onset. In a study involving 146 children, melatonin was administered 45 minutes before bedtime. The results indicated a significant reduction in sleep onset latency, with children falling asleep faster compared to the placebo group . This demonstrates that melatonin can begin to work within an hour in this population.
Patients with Delayed Sleep Phase Syndrome (DSPS)
In patients with DSPS, melatonin administered 5 hours before the individual’s dim light melatonin onset (DLMO) advanced sleep onset by approximately 1.5 hours. This study involved 30 patients and showed that melatonin significantly decreased sleep latency and improved subjective sleep quality . Therefore, for DSPS patients, melatonin can start to work within a few hours, particularly when timed correctly relative to their DLMO.
Elderly Patients with Insomnia
Elderly patients with primary insomnia also benefit from melatonin, particularly prolonged-release formulations. A study involving 791 adults aged 18-80 years found that prolonged-release melatonin (PRM) significantly reduced sleep latency in elderly patients over a 3-week period . This indicates that melatonin can start to work within a few weeks, with sustained benefits over longer periods.
Conclusion
Melatonin generally begins to work within 30 minutes to a few hours, depending on the population and specific sleep disorder. In healthy individuals and children with neurodevelopmental disorders, melatonin can reduce sleep onset latency within an hour. For patients with DSPS, timing the dose relative to DLMO is crucial for optimal results, typically showing effects within a few hours. Elderly patients with insomnia may experience benefits within a few weeks, especially with prolonged-release formulations. Understanding these timelines can help tailor melatonin use for effective sleep management.
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