From the Science of Cannabis Clinicians site (which is a great source of information on all things research)
From research out of Israel, and published in the October, 2013 issue of Clinical Gastroenterology and Hepatology, comes this controlled trial showing that a short course (8 weeks) of THC-rich cannabis produced significant clinical, steroid-free benefits to 10 of 11 patients with active Crohn’s disease, compared with placebo, without side effects.
The short article links to a pdf of the study.
Of course, we think that combining it with fresh ginger reduced into a lozenge further increases the beneficial properties of both. Something you might drop into your tea or coffee if you like.