msm

MSM (methylsulfonylmethane) is a sulfur-containing compound sold as a dietary supplement, either on its own or combined with other ingredients such as glucosamine. NCCIH describes it as chemically related to DMSO (dimethyl sulfoxide), a separate substance that is applied to the skin. MSM products are typically marketed in connection with osteoarthritis and joint health, though that is a marketing focus rather than a proven use.

According to NCCIH, only a small amount of research has been done on MSM (and the related substance DMSO) for osteoarthritis, and no conclusions can be reached about whether it is helpful. In short, the evidence is limited and does not establish that MSM treats, prevents, or improves any condition. People may use it for joint discomfort, but a benefit has not been demonstrated.

Authoritative US-government sources do not establish a proven effective dose for MSM, so no specific amount is recommended here. Labeled doses vary widely between products. Talk with your doctor or pharmacist before starting MSM, especially if you have a health condition, are pregnant or breastfeeding, or take other medications.

NCCIH states that the safety of MSM is uncertain because little research has been done on this topic, which also means its long-term safety has not been well studied. Anyone considering MSM, particularly for osteoarthritis, should consult their health care provider first.

NCCIH lists possible side effects of MSM that include allergic reactions, digestive problems, and skin rashes. Because the supplement has not been thoroughly studied, other effects cannot be ruled out. Stop use and seek medical advice if you have a reaction.

The NCCIH page reviewed here does not describe specific drug interactions for MSM, and rigorous interaction data are limited. Because supplements can still interact with medications, tell your doctor or pharmacist about any prescription drugs, over-the-counter products, or other supplements you take before using MSM.