The Best Available Treatments for Cannabinoid Hyperemesis Syndrome: Benzodiazepines, Haloperidol, and Capsaicin

Systematic review searching Medline, PsycINFO, DARE, OpenGrey, Google Scholar, and the Cochrane Library from inception to February 2017. Evidence was graded using Oxford Center for Evidence-Based Medicine guidelines. 1,262 articles were screened, 63 included.

CHS has become increasingly common with cannabis legalization, yet emergency physicians and clinicians have had little evidence-based guidance for treatment. This systematic review provides the most comprehensive summary of treatment options available, even though the evidence base remains limited to mostly case reports.

CHS represents a clinical challenge because it defies the usual antiemetic approach. The finding that benzodiazepines and antipsychotics outperform traditional antiemetics suggests CHS involves different neural pathways than standard nausea and vomiting. The emergence of topical capsaicin as a treatment option is particularly interesting, as it provides a non-sedating alternative.

The vast majority of evidence comes from case reports and case series (level 4-5), the weakest forms of clinical evidence. No randomized controlled trials existed at the time of this review. Publication bias likely favors reporting of successful treatments. The heterogeneity of dosing, timing, and outcome measures across studies limits firm conclusions.