Cannabinoid hyperemesis: a case series of 98 patients.

OBJECTIVE: To promote wider recognition and further understanding of cannabinoid hyperemesis (CH).

PATIENTS AND METHODS: We constructed a case series, the largest to date, of patients diagnosed with CH at our institution. Inclusion criteria were determined by reviewing all PubMed indexed journals with case reports and case series on CH. The institution's electronic medical record was searched from January 1, 2005, through June 15, 2010. Patients were included if there was a history of recurrent vomiting with no other explanation for symptoms and if cannabis use preceded symptom onset. Of 1571 patients identified, 98 patients (6%) met inclusion criteria.

RESULTS: All 98 patients were younger than 50 years of age. Among the 37 patients in whom duration of cannabis use was available, most (25 [68%]) reported using cannabis for more than 2 years before symptom onset, and 71 of 75 patients (95%) in whom frequency of use was available used cannabis more than once weekly. Eighty-four patients (86%) reported abdominal pain. The effect of hot water bathing was documented in 57 patients (58%), and 52 (91%) of these patients reported relief of symptoms with hot showers or baths. Follow-up was available in only 10 patients (10%). Of those 10, 7 (70%) stopped using cannabis and 6 of these 7 (86%) noted complete resolution of their symptoms.

CONCLUSION: Cannabinoid hyperemesis should be considered in younger patients with long-term cannabis use and recurrent nausea, vomiting, and abdominal pain. On the basis of our findings in this large series of patients, we propose major and supportive criteria for the diagnosis of CH.