Glucosamine supplements often include MSM, or methylsulfonylmethane, in order to provide more pain relief and support of muscles and tendons along with the benefits of glucosamine, according to Drugs.com. Either on its own or with chondroitin, glucosamine only aids joint mobility and flexibility.
Glucosamine and chondroitin supplements are often used as treatment for arthritic conditions or to support the joints of those who endure heavy physical exertion on a regular basis, explains Drugs.com. While the flexibility and joint health benefits are useful in both these cases, osteoarthritis often causes pain and swelling, which is only minimally addressed by glucosamine. The addition of methylsulfonylmethane to the glucosamine supplements aids in the reduction of pain and inflammation in the joints. This increases the effectiveness and appeal of such products by expanding their utility.
As with any supplement, it is important to consult a doctor regarding the use of glucosamine supplements with MSM, warns Drugs.com. Although MSM is naturally occurring, some people have sulfa or sulfanomide allergies that make taking MSM unsafe. MSM is also a concern for patients who are pregnant, trying to become pregnant, or breastfeeding. Diarrhea, headache and nausea are common side effects of MSM usage. More severe side effects come from allergic reactions to MSM and require immediate medical attention.