Cannabis sativa has long been known for its psychotropic effect. Only recently with the discovery of the cannabinoid receptors, their endogenous legends and the enzymes responsible for their synthesis and degradation, the role of this ‘endocannabinoid system’ in different pathophysiologic processes is beginning to be delineated. There is evidence that CB_1 receptor stimulation with synthetic cannabinoids or Cannabis sativa extracts rich in ?~9-tetrahydrocannabinol inhibit gastric acid secretion in humans and in experimental animals. This is specially seen when gastric acid secretion is stimulated by pentagastrin, carbachol or 2 deoxy-D-glucose. Cannabis and/or cannabinoids protect the gastric mucosa against noxious challenge with non-steroidal anti-inflammatory drugs, ethanol as well as against stress induced mucosal damage. Cannabis/cannabinoids might protect the gastric mucosa by virtue of its antisecretory, antioxidant, anti-inflammatory, and vasodilator properties.