Common herbal teas and supplements can weaken your prescription drugs
Zambrano-Villacres R, Montenegro-Acosta W, Rodriguez-Veintimilla D, Rodriguez-Larraburu E, Espro C, Bressi V.
Medicinal Plants
That St. John's Wort or green tea you're growing on the windowsill for a soothing cup can quietly cancel out blood thinners, birth control, or cancer immunotherapy if you're also taking prescription medication.
Researchers combed through a decade of medical studies to find out what actually happens when people mix everyday medicinal plants with prescription drugs. They found that nearly a third of the studies showed real, clinically meaningful problems, mostly the herbs making drugs less effective, but sometimes raising bleeding risk or causing liver and hormone issues. The biggest offenders were plants many gardeners grow or brew at home: green tea, St. John's Wort, borage, and licorice root.
Key Findings
Out of 47 qualifying studies, 31.9% reported clinically relevant herb-drug interactions
Reduced plasma drug levels were the most common consequence, occurring in 40% of interaction cases
Camellia sinensis (green tea), Hypericum perforatum (St. John's Wort), Borago officinalis (borage), and Glycyrrhiza glabra (licorice) were the plants most often implicated
chevron_right Technical Summary
A review of global research found that common medicinal plants like green tea, St. John's Wort, borage, and licorice root can dangerously interact with prescription medications, most often by weakening the drug's effect in the body.
Abstract Preview
Original paper
Herb-drug interactions with clinical impact: A systematic review of global clinical evidence on medicinal plants widely used in Ecuador.
<h4>Ethnopharmacological relevance</h4>The widespread use of medicinal plants in Ecuador increases the risk of herb-drug interactions, many of which may compromise patient safety. Understanding cli...
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