Cannabis has been used for medicinal purposes across the world for centuries. It was included in the U.S. Pharmacopeia (Extractum Cannabis) in the mid-1800s and prescribed for a variety of conditions . By the early 20th century, states began to individually outlaw cannabis. This was at least in part due to racism in that the smoked form of the drug was introduced by Mexican immigrants . The federal government developed a series of statutes banning cannabis beginning in the 1930s. Medical cannabis was removed from the U.S.