Sorry, I've not read all the replies, but we have had great success using Clean Horse
The man who makes it is out of Arkansas. My best horse got a very aggressive sarcoid, which is a viral condition, 2 yrs ago. I used Clean Horse, and the sarcoid shrunk and disappeared in 2 weeks. There are several companies who make a similar salve. I like this particular blend because it has dmso. The bloodroot is an essential ingredient, and Clean Horse is made with bloodroot.
Years ago, one my husband's best horses got sarcoids. The vet removed them, and they came back with a vengeance. He had to sell the horse. This product is money well spent if you're dealing with sarcoids, or any other type of skin growth. It also gets rid of warts & melanomas.