Melatonin (0.1-0.5 mg physiological dose)

Tier 1 — strong evidence · Sleep onset · Jet lag · Circadian · Low dose · No grogginess

At 0.1–0.5 mg, melatonin supplementation achieves blood levels matching natural nighttime peaks (50–200 pg/mL), unlike the supraphysiological 10–100x elevations produced by 5–10 mg commercial tablets. Small dose-response studies (Zhdanova and colleagues) demonstrate that 0.3 mg is adequate for sleep-onset effect; European, Canadian, and Australian regulators endorse this low-dose range as the evidence-supported approach. Higher doses produce more residual sedation without added sleep benefit. Key caveat: melatonin interacts with anticoagulants, immunosuppressants, and CNS sedatives —…

Dose: 0.1–0.3 mg for nightly sleep onset; 0.5 mg for jet-lag adjustment. Take 30–60 min before target sleep time.