Drug interactions
Melatonin + Promethazine
Severity: Minor
Melatonin and Promethazine: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Melatonin promotes sleepiness and promethazine is strongly sedating, so combined use can increase drowsiness and next-day impairment. The effect is usually mild.
What this interaction means in plain words
Melatonin and Promethazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Melatonin belongs to Gastrointestinal Tract; Promethazine belongs to Respiratory.
Why it happens
Additive sedation through melatonin receptor agonism and histamine H1 blockade.
What to do
Counsel patients about additive drowsiness and advise against driving or operating machinery until the response is known.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Promethazine
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
- Amiodarone + Promethazine Major
- Amisulpride + Promethazine Major
Other interactions of Melatonin
- Fluvoxamine + Melatonin Major
- Alfentanil + Melatonin Moderate
- Belladonna and opium + Melatonin Moderate
- Buprenorphine buccal + Melatonin Moderate
- Butabarbital + Melatonin Moderate
- Butalbital + Melatonin Moderate
Frequently asked questions
Can I take Melatonin with Promethazine?
MediHelp rates the interaction as minor. Melatonin and Promethazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Melatonin promotes sleepiness and promethazine is strongly sedating, so combined use can increase drowsiness and next-day impairment. The effect is usually mild.
How serious is the interaction between Melatonin and Promethazine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Counsel patients about additive drowsiness and advise against driving or operating machinery until the response is known.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Promethazine page.
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