Melatonin (high-dose, nightly)

Tier 3 — weak evidence · Sleep dependency · Hormone disruption

Different from the low-dose use on the physiological-dose card (Tier 1) and the general melatonin card (Tier 2). Taking doses above 1 mg nightly can suppress your body's own melatonin production and disrupt your natural sleep-wake cycle. Long-term nightly use hasn't been well studied. Use the lowest effective dose (0.3 to 1 mg) only when needed for jet lag or shift work.

Dose: AVOID >1 mg nightly long-term; use 0.3–1 mg situationally only (jet lag, shift work)