Research

Hormonal

Exogenous melatonin advances sleep-wake rhythm and endogenous melatonin onset in patients with Delayed Sleep Phase Disorder (DSPD) when administered chronobiologically timed (approximately 5 hours prior to Dim Light Melatonin Onset).

For individuals with DSPD, taking melatonin approximately 5 hours before their natural sleep onset time (DLMO) effectively shifts their internal clock earlier, leading to earlier sleep onset and advanced melatonin production. This requires identifying one's natural melatonin onset time.

GoodSupportsHIGH confidence
Melatonin is effective in advancing sleep-wake rhythm and endogenous melatonin rhythm in delayed sleep phase disorder.
Ingeborg M. van Geijlswijk et al. · SLEEP · 2010

Why this rating

Meta-analysis of 9 randomized controlled trials, though limited by small sample sizes in adults.

Source

The Use of Exogenous Melatonin in Delayed Sleep Phase Disorder: A Meta-analysis

Ingeborg M. van Geijlswijk et al. · SLEEP · 2010

DOI 10.1093/sleep/33.12.1605

Meta-analysis · 9 studiesCited 264×
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DOI resolved against Crossref · corpus check 2026-06-10

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