I looked into it as Hank has a small skin tag that we presume to be a sarcoid on his sheath, vet said to leave alone unless it grew or bothered him but I thought getting a supplement might be worth a try, I think it was global herbs "sarc-ex' that got good reviews in that after a few weeks/months many had just shriveled up and fallen off and that was the end of it, I haven't got around to trying it yet.
I used Newmarket cream on a nodular sarcoid. It sort of melted the skin and shelled the nodule out leaving a small wound that healed completely and relatively quickly. It never came back. It seems like nasty stuff but the mare in question didn't seem to mind having it applied.