[Cannabinoid hyperemesis syndrome].

A 22-year-old man was referred to our clinic with a 7-year history of episodes of severe vomiting interspersed with symptom-free periods. We saw another patient, a 22-year-old woman, after she had been admitted for the second time with dehydration and hypokalaemia following severe vomiting. We saw a third patient, a 25-year-old woman with a personality disorder and cannabis addiction, after she had gone to the casualty department following several days of persistent excessive vomiting. All three patients seemed to be suffering from cannabinoid hyperemesis syndrome. This is a rarely described syndrome, characterised by the triad of chronic cannabis abuse, unexplained cyclical excessive vomiting and compulsive taking of hot baths for symptom relief. A subgroup of chronic frequent cannabis users suffer from this syndrome, which can appear for the first time several years after initial cannabis use. The exact mechanism of origin is unknown, though various theories exist. In the case of unexplained chronic symptoms of nausea and vomiting our advice is always to question the patient about substance misuse, and showering and bathing habits.