I forgot to mention, the MSM molecule has "carrier" properties, ie anything you take WITH MSM will penetrate the tissues of the body more effectively, due to its sulfur. For our horse owner friends, this is exactly like using a DMSO, dimethylsulfoxide.
Anyway, the important thing is that if you take MSM in conjunction with an opiate, it may lower the toxic threshold, making less of the drug more powerful and therefore potentially more dangerous.
BE CAREFUL!