Drug interactions
Melatonin + Phenylephrine po
Severity: Minor
Melatonin and Phenylephrine po: 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
Oral phenylephrine is a decongestant with mild stimulant effects, whereas melatonin is sleep-promoting. Any interaction is a minor opposition of effects without established clinical consequence.
What this interaction means in plain words
Melatonin and Phenylephrine po have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Opposing pharmacodynamic effects on arousal; no established pharmacokinetic mechanism.
What to do
No action is generally required. Avoid taking the decongestant close to bedtime if it disturbs sleep.
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 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 Phenylephrine po?
MediHelp rates the interaction as minor. Melatonin and Phenylephrine po have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Oral phenylephrine is a decongestant with mild stimulant effects, whereas melatonin is sleep-promoting. Any interaction is a minor opposition of effects without established clinical consequence.
How serious is the interaction between Melatonin and Phenylephrine po?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No action is generally required. Avoid taking the decongestant close to bedtime if it disturbs sleep.
What other medicines interact with Melatonin?
MediHelp also lists interactions of Melatonin with, for example, Fluvoxamine, Alfentanil, Belladonna and opium. The full list is on the Melatonin page.
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