Melasyl (Prolonged-Release Melatonin) for Insomnia in Older Adults
Direct Answer
Prolonged-release melatonin 2 mg (Melasyl/Circadin) is modestly effective for treating insomnia in adults ≥55 years, reducing sleep latency by approximately 19–24 minutes and improving sleep quality and morning alertness, though the American Academy of Sleep Medicine gives only a weak recommendation due to very low quality evidence. 1, 2, 3
Evidence Quality and Guideline Position
The 2017 American Academy of Sleep Medicine guideline provides a weak recommendation against routine melatonin use for chronic insomnia, citing very low quality evidence from meta-analysis of three trials in older adults (>55 years) that showed no clinically significant improvement in overall sleep quality (standardized mean difference +0.21; CI: −0.36 to +0.77). 1
However, individual high-quality trials demonstrate clinically meaningful benefits: a 354-patient randomized controlled trial found 26% responder rate (combined improvement in sleep quality and morning alertness) versus 15% with placebo (p=0.014), plus significant reduction in sleep onset latency of 24.3 minutes versus 12.9 minutes with placebo (p=0.028). 3
The discrepancy exists because guideline meta-analysis used conservative thresholds and pooled heterogeneous outcome measures, while individual trials showed consistent benefits in patient-centered outcomes including quality of life improvement (p=0.034). 1, 3
Dosing Strategy
Starting Dose
Begin with prolonged-release melatonin 2 mg taken 1–2 hours before the intended bedtime; this timing mimics physiological nocturnal melatonin secretion and optimizes circadian synchronization. 2, 4, 5
The 2 mg dose has the strongest evidence base across multiple trials in patients ≥55 years and is the only dose formally approved in the EU for this indication. 1, 4, 3
Dose Escalation
If sleep latency or quality does not improve after 3 weeks on 2 mg, increase to 3 mg nightly; further escalation to 5 mg may be considered, though evidence beyond 2 mg is limited. 2, 6
The maximum dose supported by clinical data is 5 mg, with most efficacy clustering around 2–3 mg in older adults; doses above 5 mg lack systematic study in this population. 2, 5
Duration
- Treatment may continue for up to 13 weeks based on regulatory approval; longer-term use (6 months) has been studied and shows sustained efficacy without tolerance, dependence, rebound insomnia, or withdrawal symptoms. 4, 3
Expected Clinical Benefits
- Sleep onset latency reduction: 19–24 minutes compared to placebo 1, 3
- Improved sleep quality: 26% responder rate (combined sleep quality and morning alertness improvement) versus 15% placebo 3
- Enhanced morning alertness and daytime function without next-day psychomotor impairment, memory deficits, or driving impairment 4
- Quality of life improvement measured by WHO-5 well-being index (p=0.034) 3
Safety Profile
Melatonin demonstrates a favorable safety profile in older adults with adverse event rates comparable to placebo across doses up to 6 mg and treatment durations of several months; the only frequent side effect is intended drowsiness when taken at the appropriate time. 2, 4, 7
No clinically relevant drug-drug interactions have been identified with common geriatric medications including SSRIs, beta-blockers, or other CNS-active agents, though monitoring for additive sedation is prudent. 2
No evidence of dependence, tolerance development, rebound insomnia upon discontinuation, or withdrawal symptoms in trials up to 6 months. 4, 5
Integration with First-Line Therapy
Cognitive Behavioral Therapy for Insomnia (CBT-I) remains first-line treatment for chronic insomnia in older adults per the American Geriatrics Society (strong recommendation); melatonin should be used as an adjunct, not a replacement. 2, 8
Core CBT-I components—stimulus control, sleep restriction (time in bed ≈ total sleep time + 30 minutes), relaxation techniques, and cognitive restructuring—produce superior long-term outcomes and should be initiated before or alongside melatonin. 2
When Melatonin Is Most Appropriate
Melatonin is particularly effective in elderly patients with documented low endogenous melatonin production, which declines with age and is further reduced in older insomniacs. 4, 5
Consider melatonin preferentially for sleep-onset insomnia rather than sleep-maintenance insomnia; the evidence for reducing wake after sleep onset is weak. 1
Melatonin may be used in patients with mild cognitive impairment or early Alzheimer's disease with sleep disorders, where it improves sleep quality and may have beneficial effects on cognitive function when prescribed early and long-term at 2–5 mg. 5
Alternative Options If Melatonin Fails
Low-dose doxepin 3–6 mg is the preferred alternative for sleep-maintenance insomnia in older adults, with moderate-quality evidence showing 22–23 minute reduction in wake after sleep onset and minimal anticholinergic effects. 2, 8
Ramelteon 8 mg (a prescription melatonin-receptor agonist) is appropriate for sleep-onset insomnia; it carries no abuse potential, is unscheduled by the DEA, and demonstrates more consistent efficacy data than over-the-counter melatonin. 2, 6
Critical Implementation Pitfalls
Using immediate-release melatonin instead of prolonged-release formulations diminishes effectiveness for the predominant sleep-maintenance insomnia pattern in older adults; prolonged-release mimics physiological secretion and sustains levels throughout the night. 2, 4
Administering melatonin at bedtime rather than 1–2 hours beforehand fails to optimally synchronize circadian rhythms and reduces therapeutic efficacy. 2, 4
Neglecting to initiate CBT-I before or alongside melatonin forfeits the durable benefits that behavioral therapy provides and limits long-term success. 2
Medications to Avoid
Over-the-counter first-generation antihistamines (diphenhydramine, doxylamine) should be avoided due to lack of efficacy, pronounced anticholinergic side effects (confusion, urinary retention, falls, delirium), and rapid tolerance development within 3–4 days. 2
All benzodiazepines are contraindicated in older adults because of high risks of dependence, falls, cognitive impairment, respiratory depression, and increased dementia incidence. 2, 8
Trazodone should be avoided for insomnia in the elderly because it reduces sleep latency by only ~10 minutes, does not improve subjective sleep quality, and produces adverse events in roughly 75% of older patients. 2