First get your Ulcerative Colitis under control, then try to take the olive leaf extract (maybe it will also cure your colitis).
You didn't mention anything about if you are taking
probiotics (good bacteria), which you should be taking.
Last week, I heard about a product that helps with bowel problems called Flor Essence by the company called Flora. It contains a combination of herbs: burdock root (which is a natural antibiotic), slippery elm (which reverses leaky gut syndrome and balances the PH), Turkish Rhubarb, Red Clover, Blessed Thistle, Kelp (gets rid of toxins, and protects against radiation), watercress, and sheep sorrel. Maye this product would help put your colitis into remission, so that you can then try the olive leaf extract to try to "cure" your colitis. It contains a bunch of herbs that heals leaky guy syndrome (and in colitis the contents in the gut have a potential to leak and I'm sure they do), as well as a bunch of herbs to detoxify.