Supplement × Prescription·a caution·Moderate evidence
St. John's Wort adds enzyme induction to primidone's enzyme-inducing metabolite burden and can reduce exposure to many co-medications.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
What is happening. St. John's Wort adds enzyme induction to primidone's enzyme-inducing metabolite burden and can reduce exposure to many co-medications.
Mechanism. Additive CYP and transporter induction may lower concentrations of other critical drugs.
Recommendation. Avoid unless a clinician reviews all medications for induction-sensitive interactions.
Effect on the composite score
If both Primidone and St. John's Wort are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.
Every claim on this page is cited. PMIDs link straight to PubMed.
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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
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