thanks for your reply, well the latest is that I did manage to get a band on but it came off, tried again and it stayed on for a couple of days and then once again slipped off but, the bleeding stopped and it started to scab up, it was the size of two large grapes  with marbles inside and around the base, it was dark grey in colour with no hair and rather warty like in appearance, I kept putting the neem cream on and shoving thuja tablets in plus sarcoid tablets as ordered on line from naturalpets and it was going down but, then two weeks ago we had a hot spell, the flies kept bothering it, dispite putting lots of cream on and to my horror the top split and rather like toothpaste being pushed out of a tube, a red angry piece of flesh came out of the split, (hence appealing on this forum for further advice). Basically, what I thought was a rough piece of skin under her armpit, suddenly grew into this sarcoid in May of this year, the little pony is a thoroughbred x, very fine build with no hair underneath, so in the summer the flies have a field day, even with a fly sheet etc.  When I gave her the tablets last night, I thought God, its changed shape again, its shrunk and gone flatter, almost as if someone has popped a pin into it, and its got a really crusty top, not red now or bleeding, also when I had a feel around the base of it, the marbles inside have gone down too not sure if the banding (albeit not a very good attempt) killed off some of the blood supply and thats what has reduced it or, the herbal natural remedies are now kicking on, I was warned that they can take 6 months before they can take effect.  If it starts to flare up again, then shall definately take advice from the vet and perhaps the guy you recommended,  shall keep giving her the tablets for now and am I am crossing my fingers. thanks a lot. 

My horse has sarcoids. I would advise you to consult your vet. My horse went to Leahurst and was treated under Derek Knottenbelt, he is a wonderful man and I cannot speak highly enough of himself and his team there. In my experience of sarcoids, I would not put anything on them at all without talking to a vet, or emailing Derek Knottenbelt. I sent him photo's of the sarcoids and he was able to advise my vet. Sarcoids are like treating skin cancer, they are tumours, which you will already know. They are horrible, but they in most cases (like my horse) will be there for the rest of her life, its just a case of getting them under control which will be less expense!! Good luck.