Background: The marijuana plant Cannabis has been used for centuries in the medicinal
treatment of many disorders and is still the subject of medical research and public debate.
Cannabinoids have been purported to alleviate a variety of neurological conditions such as
MS-related symptoms including spasticity, pain, tremor and bladder dysfunction. Other
neurological conditions like chronic intractable pain, dystonic movement disorders and
Tourette's Syndrome were all reported to be alleviated by cannabis use. Cannabis has been
used to treat anorexia in AIDS and cancer patients. In gastroenterology cannabis has been
used to treat symptoms and diseases including anorexia, emesis, abdominal pain,
gastroenteritis, diarrhoea, intestinal inflammation and diabetic gastroparesis.
Cannabinoids have also a profound anti inflammatory effect, mainly through the CB2 receptor.
Cell mediated immunity may be impaired in chronic marijuana users. And a potent
anti-inflammatory effect of cannabis was observed in rats . Studying the functional roles of
the endocannabinoid system in immune modulation reveals that there are no major immune events
which do not involve the endocannabinoid system. Cannabinoids shift the balance of
pro-inflammatory cytokines and anti-inflammatory cytokines towards the T-helper cell type 2
profiles (Th2 phenotype), and suppress cell-mediated immunity whereas humoral immunity may be
enhanced. They are therefore used for various inflammatory conditions including rheumatoid
arthritis and asthma. In a mouse model of colitis cannabinoids were found to ameliorate
inflammation and there are many anecdotal reports about the effect of cannabis in
inflammatory bowel disease. However, there are no methodical reports of the effect of
cannabis on inflammatory bowel disease. The aim of the proposed study is to examine in a
double blind placebo controlled fashion the effect of smoking cannabis on disease activity in
patients with IBD.