Cannabinoid hyperemesis syndrome.

The antiemetic properties of marijuana are well known, but there is increasing evidence of its paradoxical hyperemetic effects on the gastrointestinal tract and central nervous system, known as 'cannabinoid hyperemesis syndrome' (CHS). We report a case of CHS encountered in our outpatient clinic. We also completed a review of the literature using PubMed in patients over 18 years of age with CHS. Understanding the diagnostic criteria and risk factors associated with CHS may reduce the ordering of unnecessary and expensive investigations, and pursuing inappropriate medical and surgical treatments. Ultimately, abstaining from cannabis use leads to resolution of symptoms in the majority of patients. 2016 BMJ Publishing Group Ltd.