Melatonin for Delayed Sleep Phase
Verdict: Disputed
Across 5 PubMed studies, the evidence for Melatonin in Delayed Sleep Phase grades Tier B — preliminary evidence. High-quality studies disagree — the evidence is genuinely mixed.
B 🟡 B Preliminary Evidence Disputed
Why this grade7-layer evidence engine
⚖️
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.74
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
B · Disputed
Confidence
80%
Broadly consistent
Evidence level
E2
Multiple high-quality MAs (≥2 independent, consistent)
▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.745
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (2 篇 > 1 negative)
- tier_strict_requirement_check — | A→B 因 L4 有 ≥1 against
- detect_disputes — 偵測到 1 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (5)L2 · primary research & systematic reviews
Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: ASWPD, DSWPD, N24SWD, and ISWRD. An Update for 2015: An AASM Clinical Practice Guideline
Finding: The AASM systematically reviewed the evidence and issued a positive (conditional, second-tier confidence) recommendation FOR strategically timed melatonin in adults with DSWPD, while explicitly recommending AGAINST melatonin in elderly patients with dementia.
View on PubMed The use of exogenous melatonin in delayed sleep phase disorder: a meta-analysis
Finding: Pooling 9 RCTs (91 adults + 226 children), melatonin advanced sleep onset by 0.67 h (95% CI 0.45-0.89), endogenous melatonin onset by 1.18 h (95% CI 0.89-1.48) and shortened sleep-onset latency by 23.27 min (95% CI 4.83-41.72), but did NOT significantly change wake-up time or total sleep time.
View on PubMed Efficacy of melatonin with behavioural sleep-wake scheduling for delayed sleep-wake phase disorder: A double-blind, randomised clinical trial
Finding: Melatonin plus behavioural scheduling advanced actigraphic sleep onset by 34 min vs placebo (95% CI -60 to -8 min, p<0.05) and yielded clinician-rated improvement in 52.8% vs 24.0%, but dim-light melatonin onset (the circadian marker) did NOT differ significantly between groups post-treatment.
View on PubMed Optimizing the Time and Dose of Melatonin as a Sleep-Promoting Drug: A Systematic Review of Randomized Controlled Trials and Dose-Response Meta-Analysis
Finding: Across 26 RCTs (1689 observations), melatonin gradually reduced sleep-onset latency and increased total sleep time, with the model predicting greater effect from 4 mg taken 3 h before bedtime than the usual 2 mg 30 min before; abstract reports no pooled minute-level effect sizes with CIs.
View on PubMed Melatonergic agents influence the sleep-wake and circadian rhythms in healthy and psychiatric participants: a systematic review and meta-analysis of randomized controlled trials
Finding: In 38 RCTs (1294 healthy + 687 psychiatric participants), melatonergic agents significantly reduced sleep-onset latency in healthy adults (pooled SMD -0.639, 95% CI -0.968 to -0.310), an effect that was dose- and timing-dependent.
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Cautious
no basis to conclude that melatonin is GRAS source↗
L4b EU EFSA
Supportive
melatonin and reduction of sleep onset latency source↗
L4c UK NHS
Cautious
Melatonin is available on prescription only. source↗
L4d TW TFDA / 衛福部
Against
褪黑激素產品屬藥品列管 source↗
L4e WHO
Not addressed
altered melatonin excretion source↗
L5a NIH Office of Dietary Supplements
Cautious
short-term use of melatonin supplements appears to be safe source↗
L5b Mayo Clinic
Supportive
Research shows that melatonin reduces the length of time needed to fall asleep and advances the start of sleep in adults and children with delayed sleep phase disorder. In delayed sleep phase (delayed sleep-wake phase sleep disorder), the sleep pattern is delayed two hours or more from a conventional sleep pattern, causing you to go to sleep later and wake up later. source↗
L5c Cleveland Clinic
Supportive
For example, a low dose (0.5 to 1 mg) is a starting treatment. This isn't a bedtime medication; you'll need to take it four hours before your desired sleep time. Melatonin is widely available over the counter, but not all are U.S. Food and Drug Administration (FDA)-approved. Look for brands with highly reliable amounts and low fillers. Any medication additions to your routine should always be f… source↗
L5d Harvard Health
Supportive
The American Academy of Sleep Medicine (AASM) has recommended that strategically-timed melatonin be used in the treatment of delayed sleep/wake phase disorder in children and adults (without medical or psychiatric comorbidities). The AASM has recommended melatonin not be used for insomnia in adults. In the context of sleep, the use of melatonin supplements plays an important role as a chronobio… source↗
L5e Specialty Society (condition-mapped)
Supportive
In this disorder, a person's natural inclination is to fall asleep and wake up much later than what fits their environment. Lifestyle changes and a set bedtime are often suggested first, but if they do not help, a doctor may recommend trying melatonin supplements. Recommended doses are 3 to 5 mg taken 1.5 or more hours before bedtime. source↗