(Bold for FDA approved)
• Binds to Melatonin Receptors (MT1 and MT2):
• Synchronizes the sleep-wake cycle by acting on the hypothalamic suprachiasmatic nucleus (SCN), which regulates circadian rhythms.
• MT1 receptor activation: Promotes sleep onset by inhibiting neuronal firing in the SCN.
• MT2 receptor activation: Helps regulate the timing of the circadian clock.
• Immediate effects on sleep onset may be noticeable within 30 minutes to 2 hours of taking a dose, depending on the formulation and individual sensitivity.
• Full regulation of the circadian rhythm may take several days to a few weeks of consistent, nightly use.
• Common:
• Sedation, daytime drowsiness, fatigue
• Headache
• Dizziness, lightheadedness
• Nausea
• Vivid dreams or nightmares
• Uncommon/Rare:
• Irritability, nervousness
• Mood changes (e.g., mild depressive symptoms)
• Mild gastrointestinal disturbances (e.g., abdominal cramps)
• Allergic reactions (e.g., rash, itching)
• Extremely rare and generally associated with misuse or interactions:
• Severe drowsiness or lethargy, especially when combined with other CNS depressants.
• Hypersensitivity reactions (e.g., anaphylaxis).
unusual
common
• Wait
• Wait
• Wait
• Lower the dose
• Take dose at bedtime to avoid sedative effects during the day
• Switch to another agent
• Insomnia or Circadian Rhythm Disorders: 1–10 mg/day, typically 30–120 minutes before bedtime.
• Most individuals respond well to doses of 1–5 mg/day.
• Jet Lag: 0.5–5 mg/day for a few days before travel and up to several days after arriving at the destination.
• Sleep Disorders in Children (e.g., neurodevelopmental conditions): Start with 0.5–1 mg/day, titrating up to a maximum of 6–10 mg/day based on response.
• Immediate-Release Tablets/Capsules: 1 mg, 3 mg, 5 mg, and 10 mg
• Sublingual Tablets: 0.5 mg to 3 mg
• Long-term use is generally safe and effective for chronic sleep or circadian rhythm disorders when taken as directed.
• Tolerance to therapeutic effects is rare but may occur with prolonged use.
• Not Habit Forming
• No Dose Adjustment Typically Required
• Dose Should Be Reduced
• Generally Safe for Use: No direct effects on cardiac function
• Lower Doses Recommended
• Initial dose: 0.5–1 mg at bedtime, adjusted based on response.
• Maximum dose: 6–10 mg/day
• Limited data on safety; potential effects on fetal development are unknown.
• If used, restrict to low doses (0.3–1 mg/day) and only in the later stages of pregnancy.
• Discontinue melatonin if unnecessary and taper gradually to avoid circadian disruption.
• Small amounts of melatonin may pass into breast milk.
• Effects on the nursing infant are unknown but likely minimal due to the short half-life.
• Consider discontinuing melatonin or monitoring the infant for signs of sedation or feeding issues.
Based on data Published online by Cambridge University Press
Compiled by Dr. Jash Ajmera