How long for melatonin to work
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How Long for Melatonin to Work: Insights from Research
Melatonin Onset Time
Time-Dependent Hypnotic Effects of Melatonin
Research indicates that the onset time for melatonin's hypnotic effects can vary significantly depending on the time of administration. A study involving young adults found that the latency to maximum effect ranged from 3 hours and 40 minutes when taken at noon to just 1 hour when taken at 9 PM. This suggests that melatonin's effectiveness in inducing sleep is highly time-dependent, with shorter onset times in the evening1.
Immediate Release Melatonin in Children
In a study focusing on children with neurodevelopmental disorders, immediate-release melatonin was administered 45 minutes before bedtime. The results showed a significant reduction in sleep onset latency, indicating that melatonin can start to work within 45 minutes in pediatric populations2.
Low Dose Melatonin in Healthy Adults
Another study involving healthy young adults who took low doses of melatonin (0.3 mg or 1.0 mg) 2-4 hours before their habitual bedtime found that sleep onset latency was significantly decreased. This suggests that even low doses of melatonin can be effective within a few hours of administration4.
Melatonin for Specific Sleep Disorders
Delayed Sleep Phase Syndrome (DSPS)
For individuals with Delayed Sleep Phase Syndrome, melatonin administered five hours before the individual's dim light melatonin onset (DLMO) advanced the onset of the nocturnal melatonin profile by approximately 1.5 hours. This indicates that melatonin can be effective in shifting sleep phases when taken several hours before the desired sleep time5.
Primary Insomnia in Elderly
In elderly patients with primary insomnia, prolonged-release melatonin (PRM) significantly reduced sleep latency compared to placebo, with effects observed over a 3-week period. This suggests that PRM can be effective in reducing sleep onset latency in older adults, although the exact onset time was not specified3.
Long-Term Use and Safety
Prolonged-Release Melatonin in Children with Autism
A long-term study on children with autism spectrum disorder using prolonged-release melatonin (PedPRM) showed sustained improvements in sleep patterns over a 104-week period. The study did not report specific onset times but indicated that melatonin was effective and safe for long-term use8.
Safety and Tolerability
Melatonin has been shown to be generally safe with mild adverse effects. Studies have reported no significant "hangover effects" or next-day impairments, making it a viable option for improving sleep onset without major side effects4 6.
Conclusion
The onset time for melatonin to work can vary based on the time of administration, dosage, and individual differences. Generally, melatonin can start to work within 45 minutes to a few hours, with shorter onset times in the evening. It is effective for various sleep disorders, including delayed sleep phase syndrome and primary insomnia, and is safe for long-term use in both children and adults.
Sources and full results
Most relevant research papers on this topic
Melatonin possesses time-dependent hypnotic effects.
Melatonin has a time-dependent hypnotic effect, increasing sleep propensity and subjective sleepiness when administered at various times, suggesting its role in sleep-wake regulation.
RCT
Highly CitedMelatonin for sleep problems in children with neurodevelopmental disorders: randomised double masked placebo controlled trial
Melatonin can improve sleep onset latency and total sleep time in children with neurodevelopmental disorders, but does not significantly improve child behavior or family functioning.
RCT
Rigorous JournalHighly CitedNightly treatment of primary insomnia with prolonged release melatonin for 6 months: a randomized placebo controlled trial on age and endogenous melatonin as predictors of efficacy and safety
Prolonged release melatonin (PRM) is a short- and long-term effective and safe treatment for primary insomnia in elderly patients, regardless of low melatonin levels.
RCT
Large Human Trial
Very Rigorous JournalHighly CitedEffects of low oral doses of melatonin, given 2-4 hours before habitual bedtime, on sleep in normal young humans.
Low oral doses of melatonin, given 2-4 hours before bedtime, can facilitate sleep onset and stage 2 sleep without significantly altering sleep architecture in normal young adults.
RCTHighly CitedDelayed sleep phase syndrome: A placebo‐controlled cross‐over study on the effects of melatonin administered five hours before the individual dim light melatonin onset
Melatonin administered five hours before the individual dim light melatonin onset significantly advances the nocturnal melatonin profile and improves sleep quality in patients with Delayed Sleep Phase Syndrome.
RCTHighly Cited[Melatonin: Physiological and pharmacological aspects related to sleep: The interest of a prolonged-release formulation (Circadin®) in insomnia].
Circadin®, a prolonged-release melatonin preparation, can improve sleep quality and life quality in insomnia patients aged 55 years and older without rebound effects or safety concerns.
Literature ReviewMelatonin Supplementation for Six Weeks Had No Effect on Arterial Stiffness and Mitochondrial DNA in Women Aged 55 Years and Older with Insomnia: A Double-Blind Randomized Controlled Study
Melatonin supplementation improved sleep quality but did not significantly affect cardiometabolic parameters like arterial stiffness and mitochondrial DNA in women aged 55 years and older with insomnia.
RCTRigorous JournalSleep, Growth, and Puberty After 2 Years of Prolonged-Release Melatonin in Children With Autism Spectrum Disorder
Nightly PedPRM at optimal dose (2, 5, or 10 mg) is safe and effective for long-term treatment of insomnia in children with autism spectrum disorder, with no observed detrimental effects on growth or pubertal development.
RCTHighly CitedMelatonin and insomnia
Melatonin is probably of no clinical value in managing psychophysiological insomnia, with side effects including headache and odd taste in the mouth.
RCTHighly CitedSleep dysfunction in Rett syndrome: a trial of exogenous melatonin treatment
Melatonin treatment improved sleep quality and reduced sleep-onset latency in girls with Rett syndrome, with no adverse side effects observed during a 4-week treatment period.
RCTHighly Cited