To the Editor: We read with interest the article by Simonetto et al1 on cannabinoid hyperemesis (CH) that was published in the February 2012 issue of Mayo Clinic Proceedings. Indeed, this entity is underdiagnosed due to a lack of awareness. Marijuana users presenting to the emergency department with nausea, vomiting, and abdominal pain are a common occurrence; these patients typically undergo several futile investigations and present repeatedly to the hospital with similar symptoms. Many of them are branded as ”drug seekers,” especially since they might have a history of using other recreational drugs along with marijuana. We have encountered 2 patients who met the clinical criteria for CH postulated in the study by Simonetto et al, both of whom were misdiagnosed initially. Patient 1 was a 20-year-old man who presented with nausea, vomiting, and severe epigastric pain. He was initially diagnosed with pancreatitis because of a mildly elevated serum amylase level and a history of heavy alcohol use. He had been smoking marijuana daily for the preceding 2 years. After administration of intravenous hydration and opioids, his symptoms did not improve, even though his laboratory values normalized. Physical examination findings remained normal. He insisted on taking several hot showers throughout the day. The patient was deemed to be “drug seeking,” and, in fact, a psychiatry consultation was requested in view of this unusual behavior. A literature review suggested cyclic vomiting syndrome, which is exacerbated by use of marijuana. The patient had symptomatic improvement with oral pantoprazole, and he was discharged with the advice to stop using marijuana. Patient 2 was a 49-year-old man who was transferred to our hospital for evaluation of ST-segment elevation myocardial infarction. He had ST elevations in lateral electrocardiogram leads with severe epigastric pain, nausea, and diaphoresis; however, an emergent cardiac catheterization study showed normal coronary arteries. On further questioning, he reported using marijuana during the previous 3 months to increase his appetite. Since then, he had been having episodes of epigastric pain, vomiting, and diaphoresis, which usually lasted 1 to 2 days and resolved spontaneously. He had lost 5 kg over the preceding 3 months; taking a hot shower typically improved his symptoms. A prior electrocardiogram obtained at his primary care physician's office showed similar ST-segment elevation suggesting early repolarization. In view of the typical history, the patient was provisionally diagnosed with CH syndrome and was discharged with instructions to avoid marijuana. In the Table, we summarize the number of criteria proposed by Simonetto et al for the diagnosis of CH that were met by our patients. TABLE Proposed Clinical Criteria for Diagnosis of Cannabinoid Hyperemesis in 2 Patients We applaud the effort by Simonetto et al. Indeed, their set of proposed criteria are quite specific and will help make the diagnosis of CH easier to elucidate by enumerating its intriguing features. However, it should be clarified as to how many of these criteria need to be met before making a diagnosis of CH, especially since resolution of symptoms with marijuana cessation is difficult to establish because most patients choose not to undergo follow-up for various reasons.