Melatonin

Melatonin is marketed in the U.S. as a dietary supplement; FDA does not preapprove supplements for safety/effectiveness. NIH describes possible benefit for selected circadian/jet-lag settings, with condition-specific uncertainty. AASM’s 2017 adult chronic-insomnia guideline weakly recommends against melatonin for sleep-onset or maintenance insomnia based on limited, very-low-quality evidence. A sleep diagnosis and behavioral treatment assessment remain important; a retail sleep-support claim is not an approved disease indication.

Circadin: short-term primary insomnia with poor sleep quality, as monotherapy at age ≥55. Current Slenyto: insomnia after insufficient sleep-hygiene measures in ages 2–18 with ASD and/or neurogenetic disorders involving abnormal daily melatonin secretion and/or nocturnal awakenings; a separate indication covers ages 6–17 with ADHD. These are EU-authorized prescription-product indications, not blanket approval for childhood insomnia or for U.S. supplements.

No single U.S. FDA-approved insomnia dose, pediatric supplement dose or maximum is supplied here. Prescriber-selected circadian timing may differ from bedtime use; do not escalate a gummy or capsule to reproduce a foreign prescription regimen.

Assess effect after at least three months for the ASD/neurogenetic indication, and approximately three months for ADHD; consider stopping if no clinically relevant benefit. Review ongoing suitability at least every six months. The ADHD label additionally calls for regular discontinuation attempts at least yearly, particularly when benefit is uncertain. A missed dose may be taken before going to sleep that night; after that, wait until the next scheduled dose. Do not double. If a higher dose worsens effect, consider supervised reduction before abandonment.

Circadin/Slenyto tablets must remain whole to preserve prolonged release; do not crush or chew. Slenyto whole tablets may be placed in yogurt, orange juice or ice cream and taken immediately; do not store the mixture. Supplement capsules, gummies, liquids and sustained-release tablets are not automatically equivalent to either EU medicine. Check mg per unit/serving and liquid concentration; a change in brand or release design needs a new plan.

Circadin and Slenyto list hypersensitivity to melatonin or product excipients as the formal contraindication. Autoimmune/liver restrictions and inherited lactose-related restrictions appear in warnings/precautions, and should still be respected. The selected NOW capsule cautions against pregnancy/nursing and limits use to adults; these manufacturer restrictions do not constitute a standardized FDA contraindication list for all melatonin supplements.

The selected U.S. supplement has no FDA prescription-drug boxed-warning label. Circadin/Slenyto EU SmPCs are a different regulatory format and do not use an FDA boxed-warning designation. Absence of that format does not establish harmlessness or U.S. drug approval.

NIH describes headache, dizziness, nausea and sleepiness in short-term supplement studies. Slenyto reports somnolence, fatigue, headache, mood swings, irritability, aggression and next-day effects; frequency cannot be transferred to gummies. Circadin’s labeled reactions include sleepiness/dizziness and mood/dream changes, among others. Seek care for severe allergy or major behavioral change. Suspected accidental ingestion/overdose needs poison-center or urgent clinical assessment; marked drowsiness or breathing difficulty warrants emergency help. Do not assume every product mixture has the same overdose course as prescription melatonin alone.

Confirm the actual product and all medicines/supplements with the prescriber or pharmacist.

People with epilepsy or taking anticoagulants should use supplements under medical supervision. Do not independently change a beta blocker, evening NSAID or other essential medicine to manipulate melatonin; discuss the Slenyto label’s endogenous-secretion interaction observations with its prescriber. The NOW capsule also advises review with sedatives/antidepressants and relevant medical conditions.

Use the exact EU indication/age range when prescribing those products. Circadin has no established pediatric efficacy/safety; Slenyto ADHD use below six is not established and use below two for insomnia is not relevant. AASM advises pediatric clinician review before supplements and consideration of sleep schedules/behavior; when used, dose/timing and product quality should be assessed. Older patients can have greater next-day exposure/drowsiness, even where Circadin has an age ≥55 indication.

Human safety information is insufficient. The selected U.S. capsule excludes pregnancy/nursing. Circadin does not recommend use in pregnancy or when planning pregnancy and does not recommend breastfeeding during treatment. Slenyto advises avoiding pregnancy use as a precaution and an individualized choice between breastfeeding and therapy. Do not infer safety from the fact that endogenous melatonin is a hormone present in milk.

Both EU products note renal PK data gaps and recommend caution; neither supplies a validated eGFR-based adjustment table. They do not recommend hepatic-impairment use because liver metabolism and limited clinical experience raise uncertainty/exposure concerns. These restrictions must not be relaxed by copying a generic supplement dose or by treating inactive renal metabolites as proof of safety.

Melatonin-receptor signaling, principally MT1/MT2, participates in circadian and sleep regulation. Circadin/Slenyto provide exogenous prolonged-release melatonin for their specific settings. Timing relative to biological night matters; sedation alone does not establish successful treatment of a circadian disorder or correction of its cause.

EU prolonged-release information describes substantial hepatic first-pass metabolism, about 15% bioavailability and predominant CYP1A metabolism, with possible CYP2C19 contribution. Metabolites are mainly excreted in urine. Circadin’s fed-state peak is around three hours and its terminal half-life about 3.5–4 hours; Slenyto also reports a prolonged-release terminal half-life around 3.5–4 hours, distinct from shorter elimination estimates discussed in its metabolism section. Do not apply those values to an untested IR capsule, gummy or liquid.

Record bedtime, sleep latency, awakenings and next-day function; assess whether the underlying diagnosis and treatment plan fit. Check drowsiness, mood/behavior and interaction changes. For Slenyto, review response around three months and ongoing need at least every six months; ADHD treatment includes the labeled periodic discontinuation review. Do not imply routine melatonin blood levels or laboratory testing validates an OTC sleep regimen.

Use a clinician-selected timing plan and behavioral sleep measures. Compare mg per serving and ingredients at every purchase; keep products secured and away from children. AASM advises considering a USP-verified product when a clinician recommends pediatric supplementation; quality verification does not prove clinical efficacy or FDA disease approval, and no such certification is claimed for the example NOW capsule. Report unexpected effects and disclose supplements before procedures or medication changes.

NOW 3 mg vegetarian capsule lists 3 mg melatonin per capsule, with rice flour and hypromellose; selected 60-count SKU 3255, UPC 733739032553. This is a representative U.S. supplement, not a treatment endorsement, FDA approval or verified stock claim.

U.S. supplements include tablets, capsules, gummies and liquids with variable strengths/release systems. EU Circadin is a 2 mg prolonged-release tablet; Slenyto has 1 and 5 mg prolonged-release tablets. Slenyto 1 mg tablets are small pink round tablets, 5 mg tablets yellow; package identity does not replace verification. Other ingredients and serving sizes differ, including combination supplements not covered here.

NOW’s selected capsule calls for cool, dry storage after opening. Circadin: do not store above 25°C; keep in the original package to protect from light. Slenyto: do not store above 30°C. Preserve prescription prolonged-release tablets whole, respect expiry and promptly use any Slenyto whole-tablet food mixture. Keep all products away from children; use local medicine/supplement disposal guidance.