I would very much doubt it. Weed is actually a very good thing for those with IBD to take as it helps with the pain, nausea and increases your appetite. Many doctors will unofficially recommend it to their patients.
But weed smoke can cause flareups too right
But weed smoke can cause flareups too right
SWIM say No, Weed is actually good for the gut. SWIM has never heard of weed causing a Flare-UP. And has not ever had one smoking weed.