Editorial: cannabis use disorders at the emergency department, a sign of a growing cannabinoid emergency—authors' reply

We very much appreciate the commentary by Professor Törnblom on our article.1,2 In particular, we are in agreement with his exhortation to improve treatment options for cannabis use disorders, which are particularly limited. A second salient point that Professor Törnblom raises is the paradox of further cannabis use as a means to treat the “sneaky” gastrointestinal symptoms associated with cannabis abuse. The leading hypothesis for cannabis hyperemesis syndrome (CHS) suggests that chronic cannabis (particularly, high tetrahydrocannabinol [THC]) use leads to a downregulation of CB1 receptor function in the brain and can lead to disruption of the hypothalamic– pituitary axis, exaggerated stress responses3 and inducement of anxiety.4 Despite this significant dysregulation of the function of the endocannabinoid system, a forceful stimulation (such as with inhalation of high THC cannabis) may still provide some antiemetic benefit. Thus, CHS sufferers may perceive that cannabis is “the only thing that works” for acute attacks and may see cannabis as the treatment and not the ultimate cause of their symptoms. This mindset, of course, leads to further difficulty in convincing them to abstain from cannabis use, which remains the only effective longterm treatment option for this condition. Difficulties in defining and identifying CHS symptoms also exist. As Professor Törnblom's group has shown,5 symptoms of CHS may be more chronic and daily, or have more of a cyclical nature. They may also range in severity, with some managing at home, to significant hospital presentations with profound electrolyte disturbances or even intestinal intussusception.6 It is certain that many cases of CHS are not identified based on symptom pattern and history alone. In this regard, we now teach our clinical trainees that they must ask explicitly about cannabis use along with tobacco use in any history, lest CHS be missed.