Changes in Emergency Department Encounters for Vomiting After Cannabis Legalization in Colorado

September 17, 2021 

George Sam Wang, MD1Christine Buttorff, PhD2Asa Wilks, MAS3et al

JAMA Netw Open. 2021;4(9):e2125063. doi:10.1001/jamanetworkopen.2021.25063

Conclusions and Relevance  The findings of this study suggest that cannabis legalization in Colorado is associated with an increase in annual vomiting-related health care encounters with regard to exposure to these markets. It may be useful for health care clinicians to be aware of cannabis hyperemesis syndrome and inquire about cannabis use when appropriate.

Cannabinoid Hyperemesis Syndrome

Frederick Chu; Marco Cascella.Author Information

Last Update: January 16, 2021.

Cannabinoid hyperemesis syndrome (CHS) is a condition in which a patient experiences cyclical nausea, vomiting, and abdominal pain after using cannabis. This disorder is characterized by 1) several years of preceding cannabis use, predating the onset of illness; 2) a cyclical pattern of hyperemesis every few weeks to months, at which time the patient is still using cannabis and 3) resolution of the symptoms after cessation of cannabis use, confirmed by a negative urine drug screen. The almost pathognomic aspect of a patient’s presenting history is that their symptoms are relieved by hot baths or shower. This activity introduces the pathophysiology, clinical manifestation, and management of cannabis hyperemesis.

Recurring vomiting, skin discolouration: the easily overlooked thermal element of cannabinoid hyperemesis syndrome 

March 24, 2021

A pathognomonic characteristic of CHS, with 92% of affected patients reporting, compulsive hot showers and baths for symptom relief.1 Many of these patients present to the emergency department with scalding injuries from use of water with very high temperatures.5 The exact mechanism by which hot showers provide relief from CHS remains unclear. As CB1 receptors are found in the hypothalamus, it is hypothesised that warm temperatures correct the cannabis-induced disequilibrium at the thermoregulatory centres, which could explain compulsive hot bathing.3 Heat therapy with warm showers also promotes vasodilation on the skin, which causes a redistribution of congested blood from the gut with diversion to the skin, ‘cutaneous steal syndrome’, relieving splanchnic congestion which alleviates symptoms.4

Diagnostic characteristics for CHS include severe cyclic vomiting usually accompanied by abdominal pain, symptom onset preceded by at least weekly marijuana use, temporary relief of symptoms with hot bathing and resolution of symptoms with cannabis cessation.1 Supportive features include male gender, cannabis use onset in the teenage years and symptom onset in the third decade of life.1 Symptom management in the acute phase is supportive with fluid resuscitation as needed, dopamine antagonist, topical capsaicin cream to the abdomen and avoidance of narcotic pain medications.6 7 Definitive treatment of CHS is abstinence requiring cannabis cessation.8

CHS is an easily overlooked diagnosis and the thermal element of the syndrome is less explored. This case highlights the risk of burn injuries in patients with CHS and the morbidity associated with a delay in diagnosis as this patient likely underwent an unnecessary surgical procedure and repeated diagnostic investigations. A detailed history of symptom occurrence and recreational drug use is paramount as a delay in diagnosis can result in expensive medical testing, hospitalisations for symptom management and costly and at times unnecessary interventions.9

Emergency Department Visits From Edible Versus Inhalable Cannabis

April 16, 2019

Marijuana advocates put out many product claims of treatment and cures without adequate scientific proof. They also put out products without consistency in their chemicals or compounds.  In other words, dosing irregularities, chemical composition variations, and contaminants all exist within final products. Several studies have shown that many final products contain heavy metals, bacteria, fungus, insecticides, etc. (1,2) For the person who purchases these products, it is becomes a guessing game to know if your product is contaminated.

The legalization of cannabis in a growing number of states coupled with the perception that marijuana is an innocuous drug has led to significant increases in cannabis consumption, both for its recreational properties and for its alleged medicinal properties. However, cannabis use is associated with adverse health effects (1), and cannabis-related emergency department (ED) visits and hospital admissions have increased (2).

In this issue, Monte and colleagues reviewed health records from patients presenting to the UCHealth University of Colorado Hospital Emergency Department from 2012 to 2016 and found a more than 3-fold increase in cannabis-associated ED visits over this period …

Acute Illness Associated With Cannabis Use, by Route of Exposure

 April 16, 2019


There were 9973 visits with an ICD-9-CM or ICD-10-CM code for cannabis use. Of these, 2567 (25.7%) visits were at least partially attributable to cannabis, and 238 of those (9.3%) were related to edible cannabis. Visits attributable to inhaled cannabis were more likely to be for cannabinoid hyperemesis syndrome (18.0% vs. 8.4%), and visits attributable to edible cannabis were more likely to be due to acute psychiatric symptoms (18.0% vs. 10.9%), intoxication (48% vs. 28%), and cardiovascular symptoms (8.0% vs. 3.1%). Edible products accounted for 10.7% of cannabis-attributable visits between 2014 and 2016 but represented only 0.32% of total cannabis sales in Colorado (in kilograms of tetrahydrocannabinol) during that period.


Retrospective study design, single academic center, self-reported exposure data, and limited availability of dose data.


Visits attributable to inhaled cannabis are more frequent than those attributable to edible cannabis, although the latter is associated with more acute psychiatric visits and more ED visits than expected.

Cannabinoid Hyperemesis Syndrome: Public Health Implications and a Novel Model Treatment Guideline

West J Emerg Med. 2018 Mar; 19(2): 380–386.Published online 2017 Nov 8. doi: 10.5811/westjem.2017.11.36368


Per the consensus guideline, treatment should focus on symptom relief and education on the need for cannabis cessation. Capsaicin is a readily available topical preparation that is reasonable to use as first-line treatment. Antipsychotics including haloperidol and olanzapine have been reported to provide complete symptom relief in limited case studies. Conventional antiemetics including antihistamines, serotonin antagonists, dopamine antagonists and benzodiazepines may have limited effectiveness. Emergency physicians should avoid opioids if the diagnosis of CHS is certain and educate patients that cannabis cessation is the only intervention that will provide complete symptom relief.


An expert consensus treatment guideline is provided to assist with diagnosis and appropriate treatment of CHS. Clinicians and public health officials should identity and treat CHS patients with strategies that decrease exposure to opioids, minimize use of healthcare resources, and maximize patient safety.

Cannabinoid Hyperemesis Syndrome: Diagnosis, Pathophysiology, and Treatment—a Systematic Review


Cannabinoid hyperemesis syndrome (CHS) is a syndrome of cyclic vomiting associated with cannabis use. Our objective is to summarize the available evidence on CHS diagnosis, pathophysiology, and treatment. We performed a systematic review using MEDLINE, Ovid MEDLINE, Embase, Web of Science, and the Cochrane Library from January 2000 through September 24, 2015. Articles eligible for inclusion were evaluated using the Grading and Recommendations Assessment, Development, and Evaluation (GRADE) criteria. Data were abstracted from the articles and case reports and were combined in a cumulative synthesis. The frequency of identified diagnostic characteristics was calculated from the cumulative synthesis and evidence for pathophysiologic hypothesis as well as treatment options were evaluated using the GRADE criteria. The systematic search returned 2178 articles. After duplicates were removed, 1253 abstracts were reviewed and 183 were included. Fourteen diagnostic characteristics were identified, and the frequency of major characteristics was as follows: history of regular cannabis for any duration of time (100%), cyclic nausea and vomiting (100%), resolution of symptoms after stopping cannabis (96.8%), compulsive hot baths with symptom relief (92.3%), male predominance (72.9%), abdominal pain (85.1%), and at least weekly cannabis use (97.4%). The pathophysiology of CHS remains unclear with a dearth of research dedicated to investigating its underlying mechanism. Supportive care with intravenous fluids, dopamine antagonists, topical capsaicin cream, and avoidance of narcotic medications has shown some benefit in the acute setting. Cannabis cessation appears to be the best treatment. CHS is a cyclic vomiting syndrome, preceded by daily to weekly cannabis use, usually accompanied by symptom improvement with hot bathing, and resolution with cessation of cannabis. The pathophysiology underlying CHS is unclear. Cannabis cessation appears to be the best treatment

Cyclic Vomiting Presentations Following Marijuana Liberalization in Colorado

Acad Emerg Med. 2015 Jun; 22(6): 694–699.Published online 2015 Apr 22. doi: 10.1111/acem.12655


The authors reviewed 2,574 visits and identified 36 patients diagnosed with cyclic vomiting over 128 visits. The prevalence of cyclic vomiting visits increased from 41 per 113,262 ED visits to 87 per 125,095 ED visits after marijuana liberalization, corresponding to a prevalence ratio of 1.92 (95% confidence interval [CI] = 1.33 to 2.79). Patients with cyclic vomiting in the postliberalization period were more likely to have marijuana use documented than patients in the preliberalization period (odds ratio = 3.59, 95% CI = 1.44 to 9.00).


The prevalence of cyclic vomiting presentations nearly doubled after the liberalization of medical marijuana. Patients presenting with cyclic vomiting in the postliberalization period were more likely to endorse marijuana use, although it is unclear whether this was secondary to increased marijuana use, more accurate marijuana reporting, or both.

Cannabinoid Hyperemesis Syndrome

Curr Drug Abuse Rev. 2011 Dec; 4(4): 241–249.


Coinciding with the increasing rates of cannabis abuse has been the recognition of a new clinical condition known as Cannabinoid Hyperemesis Syndrome. Cannabinoid Hyperemesis Syndrome is characterized by chronic cannabis use, cyclic episodes of nausea and vomiting, and frequent hot bathing. Cannabinoid Hyperemesis Syndrome occurs by an unknown mechanism. Despite the well-established anti-emetic properties of marijuana, there is increasing evidence of its paradoxical effects on the gastrointestinal tract and CNS. Tetrahydrocannabinol, cannabidiol, and cannabigerol are three cannabinoids found in the cannabis plant with opposing effects on the emesis response. The clinical course of Cannabinoid Hyperemesis Syndrome may be divided into three phases: prodromal, hyperemetic, and recovery phase. The hyperemetic phase usually ceases within 48 hours, and treatment involves supportive therapy with fluid resuscitation and anti-emetic medications. Patients often demonstrate the learned behavior of frequent hot bathing, which produces temporary cessation of nausea, vomiting, and abdominal pain. The broad differential diagnosis of nausea and vomiting often leads to delay in the diagnosis of Cannabinoid Hyperemesis Syndrome. Cyclic Vomiting Syndrome shares several similarities with CHS and the two conditions are often confused. Knowledge of the epidemiology, pathophysiology, and natural course of Cannabinoid Hyperemesis Syndrome is limited and requires further investigation.

The Prevalence of Cannabinoid Hyperemesis Syndrome Among Regular Marijuana Smokers in an Urban Public Hospital

12 January 2018


This study suggests that approximately one‐third of patients in our large, urban Emergency Department reporting heavy marijuana use experience symptoms of CHS. In our study population, the condition appears to be most common in 18‐ to 29‐year‐olds, although there was no significant difference in gender, race, ethnicity, education level or employment status between frequent marijuana users with CHS and those without.

Cannabinoid Hyperemesis Syndrome: Reports of Fatal Cases

Epub 2018 May 16.


Cannabinoid hyperemesis syndrome (CHS) is one of the more clinically challenging effects of cannabis consumption. It is characterized by cyclic attacks of nausea and vomiting in chronic cannabinoid users and learned behavior of compulsive hot bathing. The deaths of a 27-year-old female, a 27-year-old male, and a 31-year-old male with a history of CHS are reported. The decedents had a history of cyclical nausea and vomiting, chronic cannabinoid use and negative laboratory, radiological and endoscopic findings. All presented to the emergency department with nausea and vomiting in the days preceding death and were treated symptomatically. Toxicological analysis revealed tetrahydrocannabinol in postmortem blood. The cause of death of two of the three cases was attributed to CHS. CHS was appreciated in the third case but was not the cause of death. These three cases demonstrate the importance of recognizing CHS as a potential cause or contributing factor to death in cannabinoid user.

Cannabinoid hyperemesis and the cyclic vomiting syndrome in adults: recognition, diagnosis, acute and long-term treatment?

Ger Med Sci. 2017; 15: Doc06.Published online 2017 Mar 21. doi: 10.3205/000247


We provide a reliable and feasible clinical approach towards two clinically extremely similar syndromes (CHS and CVS). This pragmatic approach encompasses the major issues of both syndromes: awareness, recognition and adequate diagnostic measures, treatment and follow-up. Additionally, this approach can generate data which is required to better understand and treat CVS and CHS.

Cannabinoid Hyperemesis Syndrome: Literature Review and Proposed Diagnosis and Treatment Algorithm

September 2011

Authors: Erik A. Wallace, MD, Sarah E. Andrews, DO, MBA, Chad L. Garmany, MD, Martina J. Jelley, MD, MSPH


Cannabinoid hyperemesis syndrome (CHS) is characterized by cyclic vomiting and compulsive bathing behaviors in chronic cannabis users. Patients are typically diagnosed with CHS only after multiple and extensive medical evaluations, consequently without a clear etiology of their symptoms or treatment plan leading to symptomatic improvement. Increased healthcare provider awareness of CHS as a cause of nausea, vomiting, and abdominal pain coupled with an attentiveness to focused history taking-especially noting symptomatic improvement with prolonged exposure to hot showers or baths-can lead to effective treatment through cannabis cessation. We propose a diagnosis and treatment algorithm for physicians to follow when evaluating patients presenting with nausea, vomiting, and abdominal pain who are suspected to suffer from CHS.

Cannabinoid-Induced Hyperemesis: A Conundrum—From Clinical Recognition to Basic Science Mechanisms

Pharmaceuticals (Basel). 2010 Jul; 3(7): 2163–2177.Published online 2010 Jul 7. doi: 10.3390/ph3072163


The clinical occurrence of cannabis-induced hyperemesis in some patients who chronically use cannabis has been well established. Traditionally, the most psychoactive component of marijuana plant, Δ9-THC, and related cannabinoid CB1 receptor agonists are viewed as agonist antiemetics and are employed in the clinic for the prevention of chemotherapy-induced nausea and vomiting in cancer patients. However, published clinical literature indicates that in some prone individuals not only acute cannabis exposure can induce vomiting, but upon chronic cannabis intake the intensity of emesis strengthens and takes a cyclic nature in such individuals. These clinical findings are supported by published preliminary data in dogs and least shrew models of emesis. This review critically examines possible pharmacokinetic and pharmacodynamic mechanisms via which the enigmatic syndrome can occur.

Cannabinoid hyperemesis: cyclical hyperemesis in association with chronic cannabis abuse


  1. J H Allen1
  2. G M de Moore2
  3. R Heddle3
  4. J C Twartz4
  5. Correspondence to:
    Dr J H Allen
    95 Main St, Woodside, South Australia, 5244, PO BOX 338 Woodside, South Australia 5244, Australia;


Background and aims: To explore the association between chronic cannabis abuse and a cyclical vomiting illness that presented in a series of cases in South Australia.

Methods: Nineteen patients were identified with chronic cannabis abuse and a cyclical vomiting illness. For legal and ethical reasons, all patients were counselled to cease all cannabis abuse. Follow up was provided with serial urine drug screen analysis and regular clinical consultation to chart the clinical course. Of the 19 patients, five refused consent and were lost to follow up and five were excluded on the basis of confounders. The remaining nine cases are presented here and compared with a published case of psychogenic vomiting.

Results: In all cases, including the published case, chronic cannabis abuse predated the onset of the cyclical vomiting illness. Cessation of cannabis abuse led to cessation of the cyclical vomiting illness in seven cases. Three cases, including the published case, did not abstain and continued to have recurrent episodes of vomiting. Three cases rechallenged themselves after a period of abstinence and suffered a return to illness. Two of these cases abstained again, and became and remain well. The third case did not and remains ill. A novel finding was that nine of the 10 patients, including the previously published case, displayed an abnormal washing behaviour during episodes of active illness.

Conclusions: We conclude that chronic cannabis abuse was the cause of the cyclical vomiting illness in all cases, including the previously described case of psychogenic vomiting.