Transplant and autoimmune immunosuppressants — cyclosporine, tacrolimus, sirolimus, mycophenolate, methotrexate — are dosed to a narrow blood level, and several are cleared by CYP3A4. That combination makes them the class where an over-the-counter capsule is most able to cause real harm.
Below is every interaction Magellan documents for this class — 7 entries across 7 supplements, each with the mechanism as the cited reference states it, how serious that reference treats it, and where to take the question next.
One caveat on how to weigh them. 4 of the 7 entries below are marked class-level caution: the source flags a broad group of drugs that share a metabolic pathway — usually CYP3A4 — rather than reporting a finding about a named medicine. Those are weaker than the entries that name a specific drug, and they are labelled so you can tell the difference rather than being quietly padded in.
Magellan’s Medication Safety Check runs entirely on your device — type the medicines you take and it flags every documented interaction in this dataset. Nothing you type is sent anywhere.
Open the Medication Safety Check →Berberine inhibits liver CYP450 enzymes (CYP3A4) that metabolize cyclosporine, which can raise cyclosporine blood levels and increase risk of toxicity; clinicians explicitly flag this combination as needing caution.
At higher doses resveratrol can systemically inhibit cytochrome P450 enzymes, potentially attenuating or altering the activity of drugs that rely on these pathways; a 2020 literature review flags this as a real but understudied interaction risk.
Quercetin has documented in-vitro antiplatelet activity and inhibits CYP3A4/P-glycoprotein, which could theoretically raise blood levels of drugs like cyclosporine or add to bleeding risk with blood thinners.
Hesperidin may inhibit P-glycoprotein drug transporters, potentially increasing absorption and blood levels of medications that are P-gp substrates.
Grape seed extract inhibits the CYP3A4 enzyme in vitro and may alter blood levels of drugs metabolized through this pathway; clinical relevance has not been determined.
Beet may alter how quickly the liver metabolizes CYP3A4-substrate drugs, potentially changing their effectiveness or side effects.
Individual polyphenols in this class of supplement (resveratrol-type and quercetin-type compounds) have documented in-vitro/in-vivo inhibition of these cytochrome P450 enzymes; combining several such polyphenols in one blend raises the theoretical risk of additively altered blood levels for CYP3A4/2C9/2D6-metabolized prescription drugs.
Medicines in this group include: Cyclosporine (Neoral, Sandimmune), Tacrolimus (Prograf, Astagraf), Sirolimus (Rapamune, Rapamycin), Mycophenolate (Cellcept, Myfortic), Azathioprine (Imuran).
Brand names are listed in brackets after the generic ingredient. If the name on your bottle is not here, the generic name on the label almost always is — and the Medication Safety Check accepts either.
These are the warning signs that go with the medication classes on this page. They are general safety-netting, not a prediction that any supplement will cause them.
If something feels seriously wrong, do not wait for an appointment. Call 911 (US) or your local emergency number.
Severity describes the interaction as the cited reference frames it, not how a specific person will react. A “minor” entry in someone with kidney disease, on five other drugs, can matter more than a “major” one in someone on nothing else.
This is a curated set of interactions with citations — not an exhaustive pharmacology database. An interaction that is absent here has not been ruled out; it may simply not be documented in the references Magellan curates from. Supplements are also not batch-tested for identity or contamination the way prescription drugs are, so what is on the label is a claim rather than a guarantee. And most of these entries come from case reports and mechanistic work rather than randomized trials, which is exactly why the sensible response is a pharmacist review rather than either alarm or dismissal.
5 documented interactions in total.
2 documented interactions in total.
2 documented interactions in total.
3 documented interactions in total.
2 documented interactions in total.
3 documented interactions in total.
3 documented interactions in total.
Blood thinners · Blood pressure medications · Diabetes medications · Statins · Cancer treatment · Antibiotics · Diuretics · Other drug classes
Back to the full supplement–drug safety hub → · The evidence-graded supplement guide →
Berberine, Resveratrol, Quercetin, Hesperidin (citrus flavonoid), Grape seed extract, Beetroot and dietary nitrate, DaVinci Labs Phyto Benefits — 7 documented entries in total (1 major, 1 moderate, 5 minor). Each entry on this page names the reference it came from.
In this dataset the class includes Cyclosporine, Tacrolimus, Sirolimus, Mycophenolate, Azathioprine. Brand names are mapped to their generic ingredient inside the Medication Safety Check, so typing the name on your bottle works.
Usually not. Most entries here call for one of three things: separating the doses by a few hours, monitoring a lab value or a home reading for a couple of weeks, or a prescriber-led dose adjustment. The decision belongs to the clinician who manages the prescription — what this page is for is making sure the conversation happens before you start rather than after something goes wrong.