As marijuana use becomes more accepted throughout the U.S. the question of whether isolated cannabis use should prevent candidacy for transplantation is arising more frequently. Clearly, anyone who behaves in a medical irresponsible manner for any reason - not showing up for appointments, skipping medications doses, etc. - will be turned down with or without the use of marijuana. But the individual who is fully compliant and acknowledges smoking pot (thereby being honest with providers!) has often been excluded. The issue is more complicated by the fact that the medical use of marijuana is legally permissible in an increasing number of states.
New Jersey Senators have just passed S-1220 to specifically prevent medical marijuana users from being ejected from transplant wait lists. http://thinkprogress.org/health/2013/03/07/1685791/new-jersey-medical-marijuana-transplant/?mobile=wt Transplant centers require such support from society to be able to effectively apply such directives. Why? Because it is the insurance carriers whose policies drive decisions behind the scenes. Even if a transplant team supports the marijuana smoking patient's candidacy, if the insurance company cannot be persuaded, unfortunately the patient won't be transplanted.
In the absence of clear evidence that marijuana use specifically harms organs transplants or interferes with the immunosuppressive drugs, this issue is likely to become a more frequent challenge. While cessation of cannabis use is to be encouraged in order to avoid any additional inhalant into lungs vulnerable to infection, it should not be required in the otherwise compliant patient. However, it should also be noted that anyone with sufficient financial means to purchase marijuana must also be able to afford all medications!