Brief History: Medical Marijuana

Some call it a green rush. In the past five years, the number of medical-marijuana dispensaries in Los Angeles has exploded from four to nearly 600. To get a handle on what one city official called a "chaotic situation," more than 400 were shuttered June 7, following a January vote to limit their numbers in response to complaints that many were catering to recreational users.

When it comes to using the drug for medical purposes, though, no one did it like the ancients. Around 2000 B.C., the Egyptians used cannabis to treat sore eyes. A millennium later, doctors in India could be found mixing the weed with milk to use as an anesthetic. In 200 B.C., the Greeks used marijuana to remedy earaches. Pot even enjoyed its freedom in America's early days. Farmers in colonial Jamestown were urged to grow hemp, and 19th century medical journals praised the plant's medical effectiveness.

Such endorsements slowed and eventually became nonexistent after 1937, when the Marihuana Tax Act effectively banned the drug in the U.S. In 1996, California approved marijuana for medical use in treating cancer, AIDS, chronic pain and other illnesses. Today 60% of Americans support legalizing it for medical use, according to an April 2010 AP-CNBC poll. As a result, states are increasingly having to grapple with whether to take this course and, if they do, how to go about prescribing and dispensing the goods. In January, New Jersey became the 14th state to legalize the drug for medicinal purposes. The law, expected to go into effect July 1, is among the most restrictive in the nation, forbidding patients to grow the drug or use it in public and limiting them to 2 oz. a month. And with a handful of other states debating legalization (a measure will be on the ballot this November in Arizona), one thing is certain: Mary Jane has not had her last dance.