Supplements and Sirolimus.
Sirolimus, sold under the brand name Rapamune, is an mTOR inhibitor used as a post-transplant immunosuppressant. The therapeutic window is narrow and CYP3A4-driven.
Sirolimus is an mTOR inhibitor immunosuppressant. The class includes sirolimus and everolimus. Mechanism differs from calcineurin inhibitors, but the therapeutic window is just as narrow and the CYP3A4 dependence is just as strong. Trough plasma levels are monitored after transplantation, or in the specific oncology indications. The same CYP3A4-active supplement exclusion list applies. Curcumin, quercetin at higher doses, resveratrol, schisandra, St John's Wort, and bergamot extract all change plasma mTOR inhibitor levels in measurable ways. Grapefruit and Seville orange are textbook exclusions and are listed in the BNF and product literature. Immune-stimulating supplements (echinacea, andrographis, elderberry, cordyceps, astragalus) work against the drug and are excluded too. Use in cancer overlaps further with the active cancer context flag in our checker, since several supplements that are otherwise lower risk become exclusions during active oncology care.
Below are the 17 documented pairs we have explicitly assessed against Sirolimus in the Distil database: 8 severe and 9 caution. The pairs cluster around 6 mechanisms: CYP induction, CYP3A4 inhibition, Reduced immunosuppressant level, Immune-stimulant vs immunosuppressant (precautionary), Immunosuppression caution, and Nrf2 + CYP modulation. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.
Documented interactions
Last reviewed 29 October 2026. Each interaction below lists the evidence its assessment drew on: some rest on studies of the exact pair, others on mechanism evidence, where a citation may support one part of the reasoning rather than the exact combination. The evidence line on each entry says which.
CYP induction
Severe Does St John's Wort interact with Sirolimus?
St John's Wort can make your body clear sirolimus faster, which lowers its level and can leave a transplant less protected against rejection. The UK product information for sirolimus names St John's Wort among the medicines that reduce its level. Do not combine them, and tell your transplant team if you have taken St John's Wort.
Evidence: Supported by human study data.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
CYP3A4 inhibition
Severe Does Berberine interact with Sirolimus?
Berberine can slow how the body clears sirolimus, which may push sirolimus blood levels higher than intended. We treat this as a do-not-combine pair outside direct transplant-team supervision.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Severe Does Bergamot Extract (BPF / Bergavit40) interact with Sirolimus?
Bergamot is grapefruit-family citrus and may raise sirolimus blood levels by slowing its clearance. We treat this as a do-not-combine pair outside direct transplant-team supervision.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Severe Does Boswellia interact with Sirolimus?
Boswellia may slow how the body clears sirolimus and raise its blood levels, with one laboratory study pointing the other way. Because the direction is unsettled and sirolimus has to stay within a narrow range, we treat this as a do-not-combine pair outside direct transplant-team supervision.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Severe Does Curcumin interact with Sirolimus?
Curcumin can slow how the body clears sirolimus, which may push sirolimus blood levels higher than intended. We treat this as a do-not-combine pair outside direct transplant-team supervision.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Severe Does Resveratrol interact with Sirolimus?
Resveratrol can slow how the body clears sirolimus, which may push sirolimus blood levels higher than intended. We treat this as a do-not-combine pair outside direct transplant-team supervision.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Severe Does Schisandra interact with Sirolimus?
Schisandra may slow how the body clears sirolimus and push sirolimus blood levels higher than intended, which risks toxicity: a closely related schisandra species roughly doubled sirolimus levels in people. Do not combine the two outside direct transplant-team supervision.
Evidence: Limited human data, from small studies or case reports.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Reduced immunosuppressant level
Severe Does Quercetin interact with Sirolimus?
Quercetin supplements may lower sirolimus blood levels, so if you take sirolimus do not start quercetin without speaking to your transplant team first. The concern runs the opposite way to most supplement interactions: the risk is too little sirolimus rather than too much, and a fall in level can let the body begin rejecting a transplant. No study has tested quercetin with sirolimus in people or in animals, so this caution comes from what quercetin does to ciclosporin, a transplant medicine handled by the same enzyme and transporter route, rather than from any measured effect on sirolimus itself.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Immune-stimulant vs immunosuppressant (precautionary)
Caution Does Elderberry interact with Sirolimus?
Sirolimus works by calming the immune system down so your body does not reject a transplant, and elderberry is taken to stimulate the immune system, so the concern is that elderberry may work against sirolimus and make it less effective. We have not identified evidence that elderberry changes sirolimus blood levels, so a routine trough test could look entirely normal even while the protection is being opposed, which is the part worth understanding here. Studies of elderberry with sirolimus have not been done, so this is a precaution drawn from how each one behaves rather than a measured effect, and it is worth clearing with your transplant team before you start elderberry.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Immunosuppression caution
Caution Does Akkermansia muciniphila (pasteurised) interact with Sirolimus?
If you take a medicine that suppresses your immune system, check with your specialist before starting any probiotic. The pasteurised (non-living) form used here lowers the usual concern, but immune data are incomplete, so a quick word with your team is the safe route.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Andrographis interact with Sirolimus?
Andrographis may shift sirolimus blood levels, and because sirolimus is dosed to a narrow target range even a modest shift matters: too little puts the graft at risk, too much brings kidney and blood-count problems. The direction is genuinely unsettled, because laboratory work shows andrographis slowing the gut enzymes and pumps that control how much sirolimus gets into you, while its effect on the immune system itself has run both ways in studies. Studies of andrographis with sirolimus have not been done, so speak to your transplant team before starting it and ask whether an extra level check is sensible.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Astragalus interact with Sirolimus?
Sirolimus works by calming the immune system down so your body does not reject a transplant, and astragalus is taken to support the immune system, so it may work against sirolimus. In one reported case with tacrolimus, a drug the body clears the same way, the tacrolimus level fell by almost half after a herbal mixture containing astragalus was added. That case involved several herbs and a different drug, so it proves little, and astragalus has not been studied with sirolimus. Do not start it without talking to your transplant team.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Bifidobacterium longum 1714 interact with Sirolimus?
If you take sirolimus, check with your specialist team before starting this strain: sirolimus strongly dampens the immune system, usually after a transplant, and in people whose defences are this weakened there have been rare cases of a probiotic organism getting into the bloodstream and causing an infection. If you are seriously unwell in hospital or have a central line (a long-term drip line into a large vein, such as a PICC), start any probiotic, this strain included, only if the team caring for you agrees. Bifidobacterium longum 1714 is a live bacterium, and the evidence that probiotics are safe for most people comes from studies of people who were not significantly immunosuppressed, so on sirolimus let your specialist team's advice decide.
Evidence: Supported by human study data.
Caution Does Cordyceps interact with Sirolimus?
Cordyceps is taken to support the immune system, but in transplant studies it adds to immune suppression rather than opposing it. Sirolimus is a narrow-range transplant medicine, so taking cordyceps on your own could shift the balance without anyone watching. Do not start or stop cordyceps without your transplant team.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Echinacea interact with Sirolimus?
Sirolimus works by calming the immune system down so your body does not reject a transplant, and echinacea is taken to support the immune system, so it may work against sirolimus. Echinacea can also change how the body clears medicines that are handled like sirolimus: in one volunteer study it sped that clearance up in the liver while slowing it in the gut, and a second found an overall speeding-up, so the effect on your sirolimus level could go either way. Echinacea has not been studied with sirolimus, so do not start it without talking to your transplant team.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Probiotics interact with Sirolimus?
If you take sirolimus, check with your specialist team before starting a probiotic: sirolimus strongly dampens the immune system, usually after a transplant, and in people whose defences are this weakened there have been rare cases of the probiotic organism getting into the bloodstream and causing an infection. If you do take one, choose a bacterial probiotic rather than a yeast-based one such as Saccharomyces boulardii, which European medicine labels rule out when the immune system is weakened. If you are seriously unwell in hospital or have a central line (a long-term drip line into a large vein, such as a PICC), start a probiotic only if the team caring for you agrees. Probiotics are live bacteria or yeast, and the evidence that they are safe for most people comes from studies of people who were not significantly immunosuppressed, so on sirolimus let your specialist team's advice decide.
Evidence: Supported by human study data.
Nrf2 + CYP modulation
Caution Does Sulforaphane (Broccoli Sprout Extract) interact with Sirolimus?
Sulforaphane activates a body-wide antioxidant pathway (Nrf2) that can also subtly affect liver enzymes responsible for clearing sirolimus. The effect at supplement doses is uncertain, but for a narrow-window drug like sirolimus the cautious path is to discuss with your transplant team before starting.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.
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How the checker decides
Every result has a source
Each pair we have assessed is cited to a published study (PMID) or the British National Formulary, so you can read the source yourself.
Four kinds of answer
Severe, caution, no known interaction, and not yet assessed. A pair we have not assessed is never shown as clear.
- Severe
- Caution
- No known interaction
- Not yet assessed
Nothing in our data is not a clearance
When nothing in our data records a problem with a pair, the result says no known interaction at typical doses, which is not a clearance: your pharmacist or GP can check the pair against your full medical history.
A full supplement review, built around you, not a generic stack.
The free checker answers one interaction question at a time. A Distil report reviews the bigger picture: your goals, diet, medications, current supplements and any blood results you provide, then shows what appears worth keeping, changing, adding or leaving out.
- what your diet already covers, so you are not adding a capsule for something food is already handling
- which evidence-graded compounds are worth considering for your goals, and which were considered but left out
- what to keep, change or stop from what you already take, plus the order to introduce anything new
- how your medications and complete supplement stack fit together, with daily timing and a clear point for reassessment
The interaction check is one section of the full report. You also get the reasoning behind each recommendation and the evidence references used.
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