Primary Research · 2020
Clinical relevance of St John's wort drug interactions revisited
Rigotti et al. · J Food Biochem, 2020
Key finding
High-hyperforin SJW induces CYP3A4 + P-gp via PXR, increasing clearance of ethinylestradiol and progestins. Low-hyperforin products (<= 1 mg hyperforin/day) showed no PK interaction in Will-Shahab et al. 2009 — suggesting product selection matters for this specific interaction. Still recommends avoiding high-hyperforin SJW with OCs.
Read the paper
Open sourcehttps://pmc.ncbi.nlm.nih.gov/articles/PMC7056460/
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