MSM (methylsulfonylmethane) has 2 documented interactions in Magellan’s curated dataset, covering Anticoagulants (blood thinners), Antiplatelet drugs, NSAID pain relievers. Each entry below gives the mechanism as the cited reference states it, the direction the risk runs, how serious that reference treats it, and what to actually do about it — which is, in every case, a conversation with the clinician or pharmacist who manages the prescription rather than a decision you make alone.
What it is. Methylsulfonylmethane (MSM), also called dimethyl sulfone or methyl sulfone, is a naturally occurring organosulfur compound found in small amounts in fresh vegetables, fruits, grains, and animal products, and is also manufactured synthetically for use as a dietary supplement. It provides a source of bioavailable sulfur and is the oxidized metabolite of dimethyl sulfoxide (DMSO).
Where it sits on the evidence. Magellan grades the supplement itself as Moderate evidence, with a typical studied dose of 2-6 g/day (typical studied range). That grade is about whether it works, not about whether it is safe alongside your medication — the two questions are independent, and this page answers only the second.
Products this covers: MSM (Methylsulfonylmethane) · MSM with OptiMSM (1,500 mg) · Glucosamine Chondroitin MSM (with OptiMSM).
How the risks cluster. Every entry on this page runs through the same mechanism — bleeding risk — which means one conversation covers all of them.
Safety and efficacy are separate questions, and this page only answers the first. For the second, the study Magellan’s coverage of MSM rests on is:
“Compared to placebo, MSM produced significant decreases in WOMAC pain and physical function impairment (P<0.05).”
A strong result does not make a supplement safe alongside your prescription, and a documented interaction does not mean the supplement does not work. Magellan grades those two things separately, and neither grade moves for a commission.
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 →MSM is sometimes flagged as having mild blood-thinning activity of its own, so combining it with prescription anticoagulants could theoretically add to bleeding risk; evidence is limited.
Medicines in this group include: Warfarin (Coumadin, Jantoven), Apixaban (Eliquis), Rivaroxaban (Xarelto), Dabigatran (Pradaxa), Edoxaban (Savaysa), Heparin (Lovenox, Enoxaparin), Acenocoumarol (Sintrom).
Possible additive effect on bleeding/GI risk when combined with regular NSAID use; documentation is limited compared to other supplement-anticoagulant interactions.
Medicines in this group include: Warfarin (Coumadin, Jantoven), Apixaban (Eliquis), Rivaroxaban (Xarelto), Dabigatran (Pradaxa), Edoxaban (Savaysa), Heparin (Lovenox, Enoxaparin), Acenocoumarol (Sintrom), Aspirin (Asa, Bayer aspirin) and 10 more.
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.
22 documented interactions across 17 supplements.
43 documented interactions across 24 supplements.
8 documented interactions · shares a drug class with MSM.
7 documented interactions · shares a drug class with MSM.
4 documented interactions · shares a drug class with MSM.
4 documented interactions · shares a drug class with MSM.
A–Z of every supplement and drug class in this dataset, plus how to read an interaction.
What the research actually shows, graded independently of affiliate commissions.
Not without checking with the prescriber or pharmacist first. Magellan's dataset grades this as a minor interaction: MSM is sometimes flagged as having mild blood-thinning activity of its own, so combining it with prescription anticoagulants could theoretically add to bleeding risk; evidence is limited. (Source: What Is MSM (Methylsulfonylmethane)? Uses and Risks.)
2 interactions are documented in Magellan's curated dataset: 2 minor. They cover Anticoagulants (blood thinners), Antiplatelet drugs, NSAID pain relievers. Absence from this list is not proof of safety — it means no interaction is documented in the references we curate from.
Magellan lists the typical studied dose as: 2-6 g/day (typical studied range). Dose matters for interactions — several of the entries on this page describe effects that only appear at supplemental rather than dietary intakes.