MSM is neither a medicine or a drug. It is a member of the sulfur family but should never be confused with sulfa drugs, to which some people are allergic. MSM has been used as a dietary supplement for several years. Acute, intermediate and long term studies indicate that MSM exhibits very low toxicity no matter how it is administered. Within limits you cannot overdose with MSM because the body will take and use whatever it needs, and after a 12 hr period flush any excess amounts from the body.
Sulfur is highly important.
Approximately half of the total body sulfur is concentrated in the muscles, skin and bones. Sulfur is necessary for making collagen, the primary constituent of cartilage and connective tissue. It is responsible for the formation of body proteins through the formation of disulfide bonds, which hold connective tissue together. MSM has been shown to add flexibility to cell walls while allowing fluids to pass through the tissue more easily. MSM enhances tissue pliability and encourages the repair of damaged skin.