Drug interactions
Melatonin + Modafinil
Severity: Minor
Melatonin and Modafinil: 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 sleep and modafinil promotes wakefulness, so they have opposing effects. Modafinil taken late in the day may disrupt sleep and blunt melatonin's benefit.
What this interaction means in plain words
Melatonin and Modafinil 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; Modafinil belongs to Central Nervous System.
Why it happens
Opposing pharmacodynamic effects on sleep-wake regulation.
What to do
Take modafinil in the morning and melatonin at bedtime, and review sleep patterns if insomnia persists.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Melatonin and Modafinil, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Modafinil
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 Modafinil?
MediHelp rates the interaction as minor. Melatonin and Modafinil 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 sleep and modafinil promotes wakefulness, so they have opposing effects. Modafinil taken late in the day may disrupt sleep and blunt melatonin's benefit.
How serious is the interaction between Melatonin and Modafinil?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Take modafinil in the morning and melatonin at bedtime, and review sleep patterns if insomnia persists.
What other medicines interact with Modafinil?
MediHelp also lists interactions of Modafinil with, for example, Lenacapavir, Leniolisib, Lorlatinib. The full list is on the Modafinil page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
