We tried it on a huge sarcoid (think cricket ball) and it changed it, but didn't make it any smaller. We then used Thuja you have to give it as often as you can (4 times a day at least) and it was gone in 2 months. When another horse came to the yard with a small sarcoid we gave Thuja and it was gone in a few weeks. Would definitely recommend. We got it straight from www.helios.co.uk who are really helpful if you phone them too.
I have been feeding Sarc-Ex to my horse since he came at the end of July. There has been a slow but significant improvement in his flat sarcoids in particular over the three months he has been here. Smaller ones have disappeared; larger ones are shrinking. It is stated that it's a long term process and for those horses that respond well to the treatment, the most visible results will appear after 6 months. I buy the big tubs - 5kg for about £105 which lasts for three months; although with advice I loaded for the first month so my first tub didn't last that long. It is also advised that you use it in conjunction with 'Restore' for the best results. However, be prepared for a very, very messy bed for the first week of use.