I have been doing rescue instillations of Lidocain, Heparin, Sodium Bicarbonate, some kind of steroid and Elmiron. My urologist recently added MSM and I am not really sure if this is common or not. Is this the same thing as DMSO? I heard DMSO really hurts but this did not hurt (although I kind of felt sick afterwards). Has anyone had MSM instillations? I am just concerned because I have heard a lot of bad things about DMSO and I don't want to continue the MSM instillations if it can potentially do harm. Any advice would be appreciated!