What is cannabinoid hyperemesis syndrome?

Gajendran M, Sifuentes J, Bashashati M, McCallum R. Cannabinoid hyperemesis syndrome: definition, pathophysiology, clinical spectrum, insights into acute and long-term management. J Investig Med 2020;66:1309-1316 (access to full text)

Associated editorial: Schey R. Cannabinoid hyperemesis syndrome: the conundrum is here to stay. J Investig Med 2020;68:1303-4 (full text)

Why was this research conducted?

Cannabinoid hyperemesis syndrome (CHS), which is characterized by stereotypical episodic vomiting and associated with abdominal pain reduced by hot baths and showers, has an overall prevalence of about 0.1% and occurs more commonly among young male adults who are regular cannabis users. Up to a third of patients with cannabis use disorder (CUD) may present with CHS. Individuals with CHS commonly report using very hot baths or showers to alleviate symptoms. With the legalization of cannabis in many jurisdictions, it is anticipated emergency departments and other healthcare setting may see an increased volume of CHS cases. It is important that healthcare providers be aware of CHS epidemiology, diagnostic criteria, pathophysiology, and management.

What do these articles add?

The article includes a review of the published literature on CHS, two case studies, and the authors’ clinical experiences at a leading American neurogastroenterology centre. In diagnosing CHS, it is important to obtain an accurate history of cannabis use in order to distinguish CHS from cyclic vomiting syndrome (CVS), which is symptomatically similar with regard to recurrent vomiting. During acute attacks, parenteral benzodiazepines have been found to be effective. For prevention and long-term management, tricyclic antidepressants are the mainstay of therapy. Behavioral treatments to achieve cannabis cessation is recommended. Long-term management depends on not just medications, but a strong working relationship, trust, and rapport between the patient and a committed and available healthcare provider. Remission of symptoms based on cannabis cessation is confirms the diagnosis of CHS relative to CVS.

Is there anything else I should know?

As noted in the accompanying editorial (Schey; see above), as cannabis use is ‘here to stay’ in western society, CHS is as well. More research is needed to determine the relationship between cannabis use and CHS, as well the most effective treatment.