Crohn's disease

Crohn's disease is a chronic inflammatory bowel disease characterized by transmural, patchy ("skip-lesion") inflammation that may affect any segment of the gastrointestinal tract, commonly the terminal ileum, producing abdominal pain, diarrhea, fistulae, strictures, and extraintestinal manifestations. Cannabinoid receptors CB1 and CB2 are expressed on enteric neurons and gut-associated immune cells, providing biological rationale for study. The Naftali et al. pilot RCT (Clin Gastroenterol Hepatol 2013) randomized 21 patients with active Crohn's unresponsive to conventional therapy to inhaled THC-rich cannabis or placebo; 10/11 cannabis-treated patients achieved clinical response (CDAI reduction ≥100) versus 4/10 placebo, but only 5 achieved full remission and the study was not powered for remission. Subsequent trials have reported symptomatic improvement without objective reductions in inflammatory markers or mucosal healing ⚠️—a symptomatic-vs-disease-modifying distinction emphasized by guideline bodies. NASEM (2017) rated the evidence as insufficient. → See also: IBD, CB2 receptor, THC, CBD.