Colazal was patented in 2000, so it's been around for 7 years. When I first started with my GI, who is terrific, he had a fit because I was on Pentasa with my left-sided UC. He quickly switched me to Colazal, which worked better for me.
If Pentasa has been working for you, I'd give it a bit more of a chance. There are "facts" and "truths" about
this disease that just don't seem to apply to all of us all the time.
Moderate to severe left-sided UC (21 cm) diagnosed 2001.
Intolerant to Asacol and rectal mesalamine preparations.
On Prednisone then Entocort 2001-2006 with only short periods off.
Current meds are Colazal, Azathioprine and Remicade.
In remission since April, 2006. Remicade has been my wonder drug.