You might try NAC (n-acetyl-cysteine). I don't know what the pseudopolyposis is but the NAC prevents colon polyps and may also be useful in your condition.
Also NAC is a best known as a liver detoxifier, so I'm sure if you start Liver Cleansing asap that will help enormously. I wouldn't worry about too much bowel cleansing first, as long as you're not constipated or obstructed - in my experience doing too much of that just released stuff back into my system and back to the liver and gave me pains there because my liver was already overloaded. I have done two Liver Flushes and will do my third tonight and am getting better, am feeling better and my skin is better. Get Andreas book "The Amazing Liver and Gallbladder Flush" (available from Amazon.com) and you'll read how all the other organs fit together with your liver. If your liver is congested you can expect your other organs to be sick too, get your liver operating at full steam again and it will help all your other organs get rid of toxic debris.