Drug interactions
Armodafinil + St john's wort
Severity: Moderate
Armodafinil and St john's wort: moderate 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
St John's wort induces CYP3A4 and P-glycoprotein, which may lower armodafinil concentrations and reduce its effect on wakefulness. The size of the effect varies with the herbal preparation.
What this interaction means in plain words
Armodafinil and St john's wort can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Induction of CYP3A4 and P-glycoprotein increases armodafinil clearance.
What to do
Monitor response and avoid the combination if efficacy declines. If St John's wort is stopped, reassess armodafinil dosing.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Armodafinil
Frequently asked questions
Can I take Armodafinil with St john's wort?
MediHelp rates the interaction as moderate. Armodafinil and St john's wort can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. St John's wort induces CYP3A4 and P-glycoprotein, which may lower armodafinil concentrations and reduce its effect on wakefulness. The size of the effect varies with the herbal preparation.
How serious is the interaction between Armodafinil and St john's wort?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor response and avoid the combination if efficacy declines. If St John's wort is stopped, reassess armodafinil dosing.
What other medicines interact with Armodafinil?
MediHelp also lists interactions of Armodafinil with, for example, Avapritinib, Elacestrant, Elbasvir / grazoprevir. The full list is on the Armodafinil page.
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