Drug interactions
Chlorzoxazone + Watercress
Severity: Minor
Chlorzoxazone and Watercress: 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
Watercress contains phenethyl isothiocyanate, which inhibits CYP2E1, the main enzyme metabolizing chlorzoxazone. Studies using chlorzoxazone as a CYP2E1 probe showed reduced clearance after watercress, so exposure to chlorzoxazone may rise with sedation as a possible consequence.
What this interaction means in plain words
Chlorzoxazone and Watercress 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 CYP2E1-mediated 6-hydroxylation of chlorzoxazone by watercress constituents.
What to do
No routine dose change is needed with dietary intake. Watch for increased drowsiness if large or regular amounts of watercress are consumed.
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 Chlorzoxazone
Frequently asked questions
Can I take Chlorzoxazone with Watercress?
MediHelp rates the interaction as minor. Chlorzoxazone and Watercress have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Watercress contains phenethyl isothiocyanate, which inhibits CYP2E1, the main enzyme metabolizing chlorzoxazone. Studies using chlorzoxazone as a CYP2E1 probe showed reduced clearance after watercress, so exposure to chlorzoxazone may rise with sedation as a possible consequence.
How serious is the interaction between Chlorzoxazone and Watercress?
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 routine dose change is needed with dietary intake. Watch for increased drowsiness if large or regular amounts of watercress are consumed.
What other medicines interact with Chlorzoxazone?
MediHelp also lists interactions of Chlorzoxazone with, for example, Alfentanil, Alprazolam, Amobarbital. The full list is on the Chlorzoxazone page.
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