Significant acute illness can follow inhaled or edible cannabis exposure

Last Updated: 2019-03-25

By Will Boggs MD

NEW YORK (Reuters Health) - Cannabis exposure, whether inhaled or edible, can lead to acute illness ranging from cannabinoid hyperemesis syndrome to myocardial infarction, according to a retrospective study.

Emergency department (ED) visits associated with cannabis use increased in Colorado after liberalization of medical cannabis in 2009 and recreational cannabis in 2014. There is little evidence about the relative potential harms of edible and inhalable cannabis products.

Dr. Andrew A. Monte from University of Colorado School of Medicine, Aurora and Rocky Mount in Poison and Drug Center, Denver, and colleagues evaluated adult ED visits associated with edible and inhalable cannabis products in their chart review of patients presenting to the University of Colorado Health Emergency Department.

Among the 449,031 visits, 9,973 included cannabis-related diagnostic codes (ICD-9-CM or ICD-10-CM), including 2,567 visits (25.7%) deemed at least partially attributable to cannabis.

Most exposures (2,194 of 2,567) were considered to be via inhalation, whereas edible ingestion was reported in 293 visits, according to the March 25th Annals of Internal Medicine online report.

The most common reasons for cannabis-attributable visits were gastrointestinal symptoms (30.7%), including cannabinoid hyperemesis syndrome, intoxication (29.7%), and psychiatric symptoms (24.7%).

Cannabinoid hyperemesis syndrome was more common in patients exposed to inhalable cannabis (18.0% versus 8.4% with edible cannabis), whereas visits related to acute psychiatric symptoms were more common in patients with edible exposure (18.0% versus 10.9% with inhalable cannabis).

Cardiovascular symptoms were also more common with edible exposure (8.0%) than with inhalable exposure (3.1%), and severe adverse cardiovascular events, including myocardial infarction and ventricular dysrhythmia, occurred with both exposures.

Between 2014 and 2016, edible products accounted for 10.7% of cannabis-attributable visits but represented only 0.32% of total cannabis sales in Colorado.

"Future studies that examine cannabis-attributable ED visits should be stratified by route of exposure and should account for population exposure to inhalable and edible products," the researchers conclude.

Dr. Nora D. Volkow, Director, National Institute on Drug Abuse, Bethesda, Maryland, who co-authored an editorial related to this report, told Reuters Health by email, "One finding that I found particularly telling was the fact the number of ED visits due to edibles (10.7%) was a stunning 33-fold higher that what would have been predicted based on the estimated market share of edible products (0.32%). This finding alone suggests that, in relative terms, edibles may present a greater potential for severe adverse acute events than inhalable cannabis, also reflecting, among others, different clinical presentations."

"It is important for physicians to understand that scientists do not yet have a clear picture of the full range of potential adverse health consequences from cannabis consumption," she said. "This is compounded by the fact that the potency of today's marijuana is significantly higher than in the 1980s, which raises questions about the relevance of past studies as well as concerns that the consequences of marijuana use may be worse now than in the past."

"It is critical for physicians to be better informed about the importance of screening for cannabis use and about the potential for associated adverse effects," Dr. Volkow said.

She added, "We had predicted back in 2014 that if policy changes are hurriedly implemented without the required input from the medical, scientific, or policy research communities, there is a very real concern that such initiatives could magnify the potential for unintended adverse consequences in the form of far ranging health and social costs. Indeed, legal drugs (alcohol and tobacco) offer a sobering perspective, for they account for the greatest burden of disease associated with drugs not because they are more dangerous than illegal drugs but because their legal status allows for more widespread exposure."

"As policy shifts toward legalization of marijuana," Dr. Volkow said, "it is reasonable and probably prudent to predict that its use will increase and that, by extension, so will the number of persons for whom there will be negative health consequences."

Dr. Monte did not respond to a request for comments.

SOURCE: http://bit.ly/2OpPUY2

Ann Intern Med 2019.