Supplements and Colchicine.
Colchicine, sold under the brand names Colcrys, Mitigare, is a cytotoxic agent.
Colchicine is a cytotoxic agent. The class is heterogeneous (alkylators, antimetabolites, anthracyclines, taxanes, platinums) and the supplement profile depends sharply on the specific agent. Two patterns sit at the top of clinical concern. First, antioxidant supplements at high dose (vitamin C IV, vitamin E, NAC, glutathione) carry a theoretical concern about blunting the reactive oxygen species damage that chemotherapy causes in tumour cells. The oncology trial evidence is mixed. Most UK centres advise against high antioxidant doses during active treatment. Second, CYP3A4 and P-glycoprotein interactions matter for the orally dosed cytotoxics (capecitabine, imatinib, sunitinib and the kinase inhibitor family). The supplements that hit transplant medicines (curcumin, quercetin, St John's Wort) carry the same plasma level concern here. The oncology pharmacist, not the GP or community pharmacist, is the gatekeeper for any new supplement during active cytotoxic therapy.
Below are the 1 documented pair we have explicitly assessed against Colchicine in the Distil database: 1 amber. The pairs cluster around 1 mechanism: Absorption interference. 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 13 June 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.
Absorption interference
Amber Does Vitamin B12 interact with ?
Long-term colchicine can reduce how well your gut absorbs vitamin B12. It does this by temporarily damaging the lining of the lower small intestine, where B12 is taken up. The effect is linked to higher doses and longer courses, and it reverses once colchicine is stopped. Short courses for a gout flare are not a concern. If you are on colchicine long term, it is worth asking your GP about a B12 blood test.
Evidence: Supported by human study data.
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 we grade severity, choose what's in scope, and what we exclude.
Every call on this page is reasoned. We publish the full rubric for severity tiers, the medication inclusion logic, the evidence grades we accept, and what we deliberately leave out. About three thousand words. Worth reading once if you use this tool more than occasionally.
Read the full methodologyA 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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Something missing?
If a supplement or medication you take isn't in our autocomplete, tell us. We go through what people flag every week and add what's missing.