NutriStack
Rivaroxaban and St. John's Wort, a conflict.
St. John's Wort potently induces CYP3A4 and P-glycoprotein, the primary metabolic pathways for rivaroxaban. This can substantially reduce rivaroxaban plasma concentrations, compromising anticoagulant efficacy and increasing thromboembolic risk.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
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What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Rivaroxaban and St. John's Wort
- Pair type
- Conflict
- Evidence (highest tier)
- Strong
- Source citations
- 2 sources
- Stack Score effect
- −10 to your Stack Score (per scored conflict row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Conflict · Strong evidence
Conflict
What is happening. St. John's Wort potently induces CYP3A4 and P-glycoprotein, the primary metabolic pathways for rivaroxaban. This can substantially reduce rivaroxaban plasma concentrations, compromising anticoagulant efficacy and increasing thromboembolic risk.
Mechanism. Hyperforin-mediated PXR activation upregulates CYP3A4 and P-glycoprotein. Rivaroxaban undergoes CYP3A4-mediated oxidative metabolism and P-gp-mediated intestinal efflux, so induction of both pathways substantially decreases its systemic exposure.
Recommendation. Avoid combining St. John's Wort with rivaroxaban. Strong CYP3A4 inducers are listed as a contraindication in rivaroxaban prescribing information. Seek alternative supplements for mood support.
Sources (2)
- Markowitz JS, Donovan JL, DeVane CL, et al. Effect of St John's wort on drug metabolism by induction of cytochrome P450 3A4 enzyme. JAMA. 2003;290(11):1500-1504. PMID 13129991
- Mueck W et al. Clinical pharmacokinetics and pharmacodynamics of rivaroxaban. Clin Pharmacokinet. 2014;53(1):1-16. PMID 23999929
Stack Score
How this pair moves the number.
Effect on the composite score
If both Rivaroxaban and St. John's Wort are in the same stack, this pair applies −10 to your Stack Score (per scored conflict row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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