Liver transplant recipients who use cannabis did not experience more adverse outcomes than nonusers, suggesting marijuana use alone should not be considered a reason for transplant denial, according to study findings published in The American Journal of the Medical Sciences.

Liver transplantation is a lifesaving treatment for people with end-stage liver disease due to hepatitis B, hepatitis C, fatty liver disease, alcohol-related liver disease or other causes. But donor livers are in short supply, and active marijuana use is often considered grounds for exclusion from the transplant list. One reason for denial is concern that cannabis users will not be able to adhere to an arduous posttransplant medical regimen. Another is that fungal infections from cannabis use could lead to complications and organ rejection. Liver transplant recipients, who take immunosuppressive drugs to prevent organ rejection, are prone to severe fungal infections, such as those caused by Aspergillus, a fungus that can grow on marijuana plants.

Forty states have legalized cannabis for medical or recreational use, and 18% of Americans used it at least once in 2019, according to the Centers for Disease Control and Prevention. Nonetheless, cannabis users are often denied transplants. The practice is so common that some states have made it illegal to deny transplants based solely on medical marijuana use.

However, there is little definite research on the link between cannabis use and liver transplant outcomes. Mohamed Shoreibah, MD, of the University of Alabama at Birmingham, and colleagues examined clinical outcomes in people who used marijuana prior to their liver transplant.

The study included 111 people who tested positive for cannabis in a urine drug screen conducted as part of the preevaluation for liver transplantation between February 2016 and January 2021. As controls, the researchers included 100 transplant recipients who did not use marijuana. Most participants (75%) were men, and they needed a transplant for a variety of reasons, including viral hepatitis, fatty liver disease and alcohol use disorder.

Of the 111 recent cannabis users, only 32 (29%) received a liver transplant. The others were denied transplants for reasons ranging from marijuana use to financial issues; 41 people were denied due to persistent cannabis use, and 11 were denied only on the basis of marijuana use.

But among people who did receive transplants, the researchers noted no significant differences in posttransplant complications or hospital readmission rates between people who used marijuana and those who did not. What’s more, pretransplant cannabis use was not linked to any posttransplant bacterial or fungal infections, poor adherence to medications or continued substance use.

“Our data indicates that marijuana is not associated with increased risk of postoperative noncompliance, other organ complications, infections or death,” wrote the study authors. “As a single factor, marijuana may not need to be a contraindication for liver transplant.”

Click here to read the study abstract in The American Journal of the Medical Sciences.

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