With so little scientific evidence that medical marijuana does what it is purported to do, it may be time to retire the medical model — at least in states like Colorado where marijuana can be legally purchased by any adult.
A recently released comprehensive review of dozens of clinical trials on medical marijuana found scant reliable evidence to support the drug's use for all but a handful of maladies.
Medical marijuana proponents argue the results don't tell the whole story because of federal barriers to legitimate research. That may be true. Both the state and feds should support and encourage more research so decisions around medical pot can be guided by high-quality evidence.
Nor do we discount the sincerity of the many personal testimonials regarding medical pot across a range of conditions.
Nonetheless, an editorial by Yale University physicians that accompanied the study in the Journal of the American Medical Association pointed out that states have generally approved medical marijuana use by relying on "low-quality scientific evidence, anecdotal reports, individual testimonials, legislative initiatives and public opinion."
Imagine if other drugs were approved this way, said the editorial, observing that medical marijuana fails to meet the standards of the U.S. Food and Drug Administration for most conditions.
Critics have long suspected that medical claims were mostly a ruse to legalize weed. If that is not the case, then medical pot should be able to prove its efficacy through the same research methods as every other medicine.
This JAMA review of 79 trials involving nearly 6,500 patients concluded medical pot helped with specific pain syndromes and spasticity from multiple sclerosis. But there was poor evidence it is good for other conditions that make up most medical marijuana programs. And meanwhile, patients suffered side effects with disturbing frequency.
Colorado is spending money on its own research. And the Obama administration has lifted some barriers to federal studies. However, if research continues to find pot is useless for many of the maladies for which it is used, states will want to revisit the extent of their support for it.
Colorado's Amendment 20, which legalized medical marijuana in 2000, lists several "debilitating medical conditions" — such as glaucoma — for which there is still apparently little or no good evidence of a true benefit. And while it would be extremely difficult to change the measure, that doesn't mean the possibility shouldn't be discussed.