In 2023, Kentucky became the most recent state to pass a law prohibiting the denial of organ transplantation to patients solely because of their marijuana use. The legislation is scheduled to go into effect Jan. 1, 2025. Over the past 11 years, similar measures have been enacted in 21 other states.
Though these laws overstep into medical decision-making, they are part of a rising trend. As cannabis use becomes increasingly prevalent in American society — in 2023, 61 million Americans smoked, vaped, or otherwise consumed marijuana — state governments are taking the lead in upholding the rights of cannabis users, including the rights to medical treatments to which they have historically been denied, such as organ transplantation.
At the same time, organ transplant societies, which set guidelines on transplant care, have passed on setting standardized directives on cannabis use, allowing individual programs to make their own rules. Some programs have taken a hardline approach, adopting zero-tolerance policies on marijuana. Other programs have been more permissive, taking a sort of “don’t ask, don’t tell” stance. Still others have settled in the middle, allowing transplant listing for cannabis users after six months of abstinence — even in states that have passed statutes prohibiting such limitations. There is no consensus on this issue in the transplant community.
The variability in approach has led to disparities. Cannabis users with adequate resources, for example, can translocate to communities where programs allow transplant listing despite substance use. Such “program shopping” rewards wealthy patients with even more access to life-saving organ transplants than they already have.
We need a standardized approach to transplant eligibility in the substantial and growing cannabis-using population. Donor organs are a national commodity. That means national guidelines, not miscellaneous (and often ambiguous) institutional policies, are essential to ensuring organs are fairly distributed without improperly denying treatment to those most in need.
When we were in medical school about 25 years ago, cannabis use was largely forbidden by transplant centers. Then, as now, the supply of donor organs did not meet societal demands, and its proper stewardship was an ethical responsibility that programs took very seriously.
Despite advances in organ harvesting and an increase in the number of donor organs in recent years (in part because of opioid-induced deaths), about 100,000 Americans today are on an organ transplant wait list, and approximately 6,000 die each year without a transplant.
If cannabis were known to adversely affect transplant outcomes, then it would be a no-brainer for programs to prohibit use. However, rigorous data on the health effects of cannabis are limited, in part because marijuana remains classified as a Schedule I drug, the most restrictive category, by the federal government.
We do know that vaping or smoking marijuana is associated with fungal infections in transplant patients. Furthermore, cannabis may complicate the immune system suppression that these patients require to prevent organ rejection. There is also anecdotal evidence that patients who use cannabis may not adhere to their complicated medication regimens.
Still, most of these studies are small and susceptible to bias, and it’s hard to draw sound conclusions from them. We need well-designed studies on cannabis to see whether it can compromise transplanted organs or worsen overall patient survival.
Until then, the best data we have suggests that a distinction should be made between occasional cannabis use and “cannabis use disorder,” which is characterized by psychological and physical addiction and may affect 3 out of 10 cannabis users. Patients with cannabis use disorder — roughly daily or near-daily use — have much worse outcomes after kidney transplantation, including higher rates of organ failure and death, in the first year post-transplant.
On the other hand, in a 2016 study of kidney transplants, there was no difference between recreational cannabis users, most of whom did not use daily, and nonusers in terms of patient or organ survival over a one-year period. A 2019 study of liver transplants also found that pretransplant cannabis use did not adversely affect outcomes after transplant, including five-year survival.
Cannabis use disorder before transplantation, however, isn’t necessarily associated with adverse outcomes, suggesting that pre-transplant addiction treatment may mitigate its harms.
All this suggests a framework for a national policy.
First, denying organ transplants to all cannabis users is unnecessarily restrictive. It may deepen historical inequities, as cannabis users are disproportionately Black, and Black patients have historically been underrepresented on transplant lists.
Rather, the guidelines should distinguish between occasional users, who comprise most of the cannabis-using population, and those with full-blown addiction. Occasional users should remain eligible for transplantation (though of course they should be encouraged to desist from using as there is little medical benefit from recreational use in this population).
Those with cannabis use disorder, on the other hand, should be ineligible for organ transplants, despite laws like the one about to go into effect in Kentucky, until after they undergo addiction counseling and rehabilitation. This will of course require additional resources, as only about one-third of transplant centers in the United States currently offer drug addiction services.
At the same time, we need more research into the health effects of cannabis, both in the transplant and non-transplant settings. The Biden administration is considering ending marijuana’s Schedule I drug status. Doing so will free up research money. Only with rigorous studies of cannabis will we be able to create the transparent and evidence-based standards needed to ensure fair organ allocation and optimal outcomes for all transplant patients.
Sandeep Jauhar, a cardiologist at Northwell Health in New York, is the author, most recently, of “My Father’s Brain: Life in the Shadow of Alzheimer’s.” Maria Avila is the medical director of the cardiac transplantation and mechanical circulatory support programs at North Shore University Hospital at Northwell Health.
