Currently, cannabis remains the most widely used illicit psychoactive substance in the world. Its main pharmacological properties are known and its use for therapeutic purpose is still expanding. Also, its acute and chronic toxicity become more described, even if some mechanisms of pharmacotoxicology still remain to clarify as the cannabinoid hyperemesis syndrome (CHS).

To describe cases of CHS, to highlight the clinical presentation and all the complexity of the medical exploration for making an accurate diagnosis.

We present a case series of CHS related to cannabis use and notified to the Parisian addictovigilance center.

Eight cases were collected between 2011 and 2016. The users are almost exclusively men (7/8), with a median age of 31 years and some of them present a history of psychiatric disorder. All of them report important daily cannabis consumption (up to 15 joints by day) with duration of consumption averaged at 10 years. All patients present recurrences of clinical signs of the syndrome including vomiting (8/8) and abdominal pains (8/8) leading to repeated hospitalizations. Despite the presence of compulsive taking hot showers notion (7/8), specific sign of the CHS, its diagnosis were made by a physician in 5 cases. Carried out medical examinations are often complete, invasive, even going to an explorative laparotomy for one patient.

The CHS remains not well known. A better understanding of this syndrome will enable better patient care while avoiding costly spending unnecessary investigations.

The authors have not supplied their declaration of competing interest.