A Systematic Review of Cannabis Use and the Development of Acute Pancreatitis

Abstract

Introduction: Cannabis is the most frequently consumed illicit drug in the world. It is more frequently consumed in those under age 35. It has been legalized or decriminalized in nearly half the United States. The first report of cannabis as a possible cause of Acute Pancreatitis (AP) was in 2004 (JOP 2004;5(1): 41-43). The aim of this systematic review is to review the potential association of cannabis use and the development of AP. Methods: A systematic review using PubMed/Medline, Embase, Scopus, and Cochrane was performed with a reference librarian. There were no language or year limitations. Search terms included “Cannabis” and “Acute Pancreatitis,” with all associated permutations. AP was defined by meeting 2 of 3 criteria in the Revised Atlanta Classification (Pain consistent with AP; amylase or lipase > 3x upper limit of normal; imaging consistent with AP). Cannabis induced AP was defined by preceding use of cannabis, and exclusion of common causes of AP when reported (alcohol, biliary, hypertriglyceridemia, medications, hereditary). Two authors reviewed each study for eligibility. The search yielded 239 results, of which 16 met inclusion criteria (1 prospective series, 1 case series, 12 case reports, 2 abstracts of case reports) dating from 2004 to 2016. Results: AP from cannabis was reported in 26 patients, 23/26 (88.5%) men, 22/26 under age 35. In 22 patients, AP correlated with increased cannabis use. Concomitant alcohol use was reported in 2 cases. Recurrent AP was reported in 12/26, related temporally to cannabis use. There are 9 reports of no further AP episodes after cannabis cessation. Genetic studies were available in 13, which were all negative. Conclusion: Cannabis is a probable cause of AP and recurrent AP, though its mechanism remains unclear. It occurs, as expected, mainly in younger patients with 84.6% under age 35. This trend is expected to increase as cannabis availability becomes more widespread. Cannabis should be included as a probable cause of toxin induced AP, and healthcare providers should consider toxicology screens for all patients with AP.