Is St. John's Wort Safe with cyclosporine?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Do not take St. John's Wort if you are prescribed cyclosporine. This combination can cause transplant rejection or treatment failure. Notify your doctor immediately if you have been taking both.
Why this interaction occurs
St. John's Wort is a potent inducer of CYP enzymes and P-glycoprotein (P-gp), which significantly increases the metabolism and clearance of cyclosporine. This reduces cyclosporine blood levels below therapeutic thresholds, risking acute organ rejection in transplant patients. This interaction is well-documented and clinically serious.
Evidence
Evidence level: strong.
Data source
PubMed - PMID 18637192
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 58,058 reports mentioning cyclosporine. This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the cyclosporine + supplement combination on this page.
FAERS reports are voluntary and cannot prove that a drug caused an event. Do not use report counts to assess the safety of this specific drug-supplement pair.
Frequently asked questions
Related interactions
All St. John's Wort interactions → · All cyclosporine interactions →
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Educational only — not medical advice.
Always confirm with your doctor or pharmacist.