Drug interactions
Grapefruit + Ketamine
Severity: Minor
Grapefruit and Ketamine: 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
Grapefruit juice can inhibit intestinal CYP3A4 and may raise exposure to orally administered ketamine. This could prolong or intensify sedation and dissociative effects. The effect is of little relevance to intravenous ketamine.
What this interaction means in plain words
Grapefruit and Ketamine 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
Inhibition of intestinal CYP3A4 by grapefruit constituents reduces first-pass metabolism of ketamine.
What to do
Advise patients taking oral ketamine to avoid large amounts of grapefruit juice. Monitor for excess sedation or psychotomimetic effects if intake is unavoidable.
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 Ketamine
Frequently asked questions
Can I take Grapefruit with Ketamine?
MediHelp rates the interaction as minor. Grapefruit and Ketamine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Grapefruit juice can inhibit intestinal CYP3A4 and may raise exposure to orally administered ketamine. This could prolong or intensify sedation and dissociative effects. The effect is of little relevance to intravenous ketamine.
How serious is the interaction between Grapefruit and Ketamine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise patients taking oral ketamine to avoid large amounts of grapefruit juice. Monitor for excess sedation or psychotomimetic effects if intake is unavoidable.
What other medicines interact with Ketamine?
MediHelp also lists interactions of Ketamine with, for example, Benzhydrocodone / acetaminophen, Brexanolone, Buprenorphine buccal. The full list is on the Ketamine page.
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