I know one of the big proponents of DMSO is A Midwestern Doctor. https://www.midwesterndoctor.com/p/dmso-is-a-miraculous-therapy-for
I’m not a member of The Forgotten Side of Medicine but at the end of the article: “In the final part of this article, I will discuss the established protocols for applying topical DMSO for many of the conditions here (including our preferred methods), key precautions to be aware of, tricks we’ve found for using it, and our preferred sources for obtaining it“.
That may be a good source to get more information.
I would definitely read the “key precautions” part. I remember learning about DMSO back around 1990 and though I haven’t kept up on it, what I understand of it is it is a solvent and allows things to absorb with it through the skin. This means that if you have any type of toxins in your environment, be wary because you may be exposing yourself through your skin to them. Just like the blood brain barrier, the skin is also a critical barrier for things to not cross through.