Studies on people who were taking infliximab for Crohn’s and also smoking or taking marijuana (weed) have shown that smoking weed in such patients increased the risk of kidney infection, fracture
and falls, bipolar disorder
and overdose of drug compared to those who did not smoke
weed. Also
weed increases the risk of gastritis and stomach pain and hence make it difficult for your doctor to monitor you.
So, yes, it would be advisable to stop it.