If you live in one of the 20 states where marijuana is legal but only for medical use, access to the drug begins at the doctor’s office. But unlike most other treatments, it is not granted via a prescription pad. 

That’s because marijuana remains a schedule 1 substance. (Physicians can only write prescriptions for schedule 2 drugs or higher.) This classification encapsulates a wider paradox: marijuana is defined as a drug with no medical value and a high potential for abuse by the federal government, but it is now legal for medical use in most states. Once dismissed as a drug for slackers, marijuana has entered the mainstream so completely it’s been embraced by wellness enthusiasts. Sixty-one percent of Americans support its legalization
 
But because the federal government continues to classify marijuana as a schedule 1 drug, along with heroin and LSD, it’s very difficult for researchers to study its health effects. While the available evidence suggests marijuana can be an effective treatment for chronic pain, the body of studies is far from robust
Meanwhile, doctors are barred from prescribing cannabis products. Instead, certified physicians in states where the drug is legal can provide patients with a medical marijuana card. 
The disconnect likely contributes to the overall confusion and lack of information surrounding marijuana’s medical benefits. Patients are increasingly curious about the drug, but doctors often don’t have answers. In a recent survey of oncologists published in the Journal of Clinical Oncology, around 80% said they’ve discussed marijuana with their patients in the past year, but only 30% felt they have enough information to advise patients on its medicinal use.
 
Even for providers who are informed about the drug and can talk knowledgeably about treatment options, such guidelines aren’t easily integrated into a patient’s health records. Because of the drug’s scheduling, doctors can suggest dosages and products (most doctors likely won’t recommend that a lung cancer patient smokes a joint, for example), but they can’t prescribe anything specific. Instead, patients visit a dispensary, card in hand, and select what they want. 
“Physicians are cut out of the loop,” said W. David Bradford,  a professor of public policy at the University of Georgia. Rescheduling marijuana would allow physicians to write cannabis prescriptions, and “integrate it into a care plan.” It would open the door, albeit a crack, for pharmaceutical companies to work with dispensaries to create more uniform doses of the product, as Sandoz has done in Canada. Patients, particularly those with complex drug regimens, could benefit from an added layer of coordination and precision.
Dr. Andrew Epstein, an oncologist with Memorial Sloan Kettering Cancer Center in New York City, supports marijuana’s use to help with pain, nausea, and fatigue after more traditional medical treatments have been tried and exhausted. But unlike Bradford, he does not feel the drug is not ready for the prescription pad treatment. 
 
Researchers simply don’t know enough about what marijuana can – and can’t – do to justify having doctors prescribe the drug in specific dosages, he said. “I’m concerned it would add to the confusion.” 
There is a lack of high-quality evidence, not to mention medical marijuana products, unlike prescription drugs, have not gone through a rigorous evaluation process by the FDA. While we have a general idea of marijuana’s effect on the body, the specifics (including the effects of individual dosages and strains) continue elude us. Writing prescriptions would add a false layer of precision to the exercise.
 
Instead, Epstein said he believes physicians should educate themselves on the available research; he also wants more clinical trials that better determine the drug’s effects. In this respect, his interests align with Bradford’s: As a schedule 1 substance, it’s incredibly difficult for researchers to obtain permission to study marijuana (and even when they do, they can only access a limited variety of strains.) A recategorization would ease these restrictions and allow for more detailed clinical trials. 
Impact on pharma
 
Despite doctor’s inability to prescribe the drug, medical marijuana is nonetheless having an effect on prescribing patterns. 
In every state where medical cannabis has been legalized it has “this benefit of people being able to use less prescription medication,” said Jessica Gelay, a policy manager at the Drug Policy Alliance. Indeed, a recent study published in JAMA Internal Medicine by Bradford and colleagues found that after states legalized medical marijuana, opioid prescriptions under Medicare Part D declined significantly. 
In those states that introduced a system of dispensary outlets, opioid prescriptions under Medicare Part D dropped by 14.5% following legalization. “People are reacting to the availability of cannabis as if cannabis was medicine,” Bradford said. “They’re doing exactly what they would do if a pharma company introduced a new blockbuster drug.”
Bradford estimates that if every state were to turn on a dispensary-based cannabis program, Medicare and Medicaid spending would drop by around $4 billion to $6 billion. Legalization represents a potentially significant “reduction in the revenue flowing to prescription drugmakers.”
Which hasn’t gone unnoticed by manufacturers. Some have publicly lashed out: Incys, an opioid maker, contributed $500,000 to an anti-legalization campaign in Arizona, for example. Others (including, ironically, Incys again) have invested in harnessing elements of the drug to create FDA-approved treatments.
The FDA is expected to green light an epilepsy medication from GW derived from marijuana later this summer. If the decision goes through, it would be the first cleared drug made from the marijuana plant, although the agency has already approved a few drugs derived from synthetic cannabinoids.
The approval would open the door for other medications derived from marijuana, particularly those, like GW’s epilepsy drug, that do not contain properties that make users high. For broad, lucrative categories such as pain management, however, marijuana-based medications could lack the financial windfall necessary to justify heavy R&D investment. 
“You can’t patent the cannabis plant,” Bradford said. Were a manufacturer to invest heavily in determining the most effective strains and dosages for treating chronic pain, “everyone could just go buy it from their local dispensary instead.”