As more states embrace legalized marijuana, the drug’s growing medicinal use has highlighted a disturbing fact for doctors: scant research exists to support marijuana’s health benefits.
Smoked, eaten or brewed as a tea, marijuana has been used as a medication for centuries, including in the U.S., where Eli Lilly & Co. sold it until 1915. The drug was declared illegal in 1937, though its long history has provided ample anecdotal evidence of the plant’s potential medicinal use. Still, modern scientific studies are lacking.
