What makes marijuana ‘medical’?
Only the intent of the user. Marijuana sold by prescription is chemically identical to the pot that stoners use as a recreational drug. Derived from the buds and leaves of the cannabis plant, marijuana contains more than 400 chemicals, one of which is THC, which works its way through the bloodstream to the brain, producing a relaxing “high.’’ Various cultures have used marijuana medicinally for thousands of years. In recent years, 13 states have legalized marijuana for medicinal purposes, and several others are currently considering it. “It’s starting to cascade,” says drug legalization advocate Ethan Nadelman. “Our model is the gay rights movement and their recent string of successes with gay marriage.”

What are pot’s medicinal uses?
There are quite a few. Marijuana is used to treat glaucoma, diabetes, multiple sclerosis, and high blood pressure, among other ailments. THC also stimulates appetite and calms the stomach in the wake of various AIDS treatments and chemotherapy, allowing patients to hold down food. Mike Stetler, a Navy veteran who lives in Huerfano County, Colo., has been using marijuana since 2002 to blunt the chronic pain resulting from a 1990 car accident. “The pain isn’t all the way gone, but I can live again,” says Stetler, who previously had relied on a battery of dangerous narcotics for pain relief.

Are there downsides to using pot in this way?
Yes. Marijuana can impede short-term memory as well as physical coordination, reasoning, and problem solving. Like tobacco, it contains carcinogens and can damage the respiratory system. There are also problems associated specifically with pot as part of a medical regimen. There is no standard dose of marijuana, for example, and its potency varies greatly. But all of these issues would be more easily addressed if the legal landscape were not so confusing.

What does the law say?
Under federal law, marijuana remains a controlled substance, so in states that have approved medical marijuana, it’s both legal and illegal. During the Bush administration, the feds regularly raided state-sanctioned pot dispensaries and indicted their owners. The Obama administration has signaled that it considers such enforcement a low priority at best. But it’s not yet clear what that means for people in the pot trade. A federal court just last week sentenced a California man to a year in jail for selling medical marijuana from a dispensary that, under state law, is legal. The dissonance doesn’t exist only in Washington; in many cases, laws aren’t applied uniformly even within states.

Why is enforcement so inconsistent?
Rules often vary from one locality to the next, depending on the prevailing attitude toward the war on drugs. Regulations on licensing and transporting pot are spotty, and the line between legal and illegal sales is often far from clear. In Michigan, where voters endorsed medical marijuana last fall, “we are simply in a state of confusion,” says Grand Valley State University criminal justice professor James Houston. “Everyone is searching for some proper guidelines.”

How do patients qualify for pot?
Essentially, they ask for it. Oregon, which legalized medical marijuana a decade ago, now has 21,000 “patients”—a fast-growing population that seems suspiciously robust for so small a state. In California, patients suffering from such routine ailments as stress and menstrual cramps have little difficulty finding a doctor to authorize marijuana therapy. Indeed, standards are so lax that even some proponents of drug decriminalization have come to view medical marijuana as a scam. “Many of the ‘dispensaries’ are about as medical as a wine store,” says UCLA drug policy expert Mark Kleiman.

What are these dispensaries like?
Some strive to look like pharmacies, with tidy vials of pot awaiting customers who have a doctor’s authorization. Others look more like hippie dens, complete with pot brownies and THC-laden lollipops for sale. But it’s big business either way. One-eighth of an ounce can be purchased for $35, with more exotic fare retailing for as much as $2,500 an ounce. Because successful dispensaries handle large volumes of cash as well as marijuana, they are prime targets for robberies and frequently deploy burly bodyguards. Some dispensary owners yearn to become mainstream. “Just because there’s a stigma attached to pot doesn’t mean that we shouldn’t be able to run our business in an intelligent fashion,” says one owner. “The biggest problem facing this industry right now is the stoner mentality.”

Is medical pot a stalking horse for legalization?
Possibly. A recent poll found a slim majority of the nation in favor of medical marijuana, and more states seem likely to follow the path to legalization. Medical marijuana will be on the ballot in Arizona next year, and in state capitals across the country, lawmakers can hear the seductive call of marijuana sales-tax revenues. But while medical marijuana has gained a foothold, decades of anti-drug policies won’t be easily surmounted. Drug tests, for example, have become commonplace in many workplaces, and employees who fail can be fired even if medical marijuana was the cause. And many Americans remain ­resolutely opposed to pot in any form. New Hampshire State Rep. William Butynski helped derail medical marijuana legislation in his state for a simple reason. “There is no such thing,’’ he insists, “as ‘medical’ marijuana.”

California dreamin’
True to form, California is at the forefront of the medical marijuana movement. Legal in the state since 1996, medicinal pot enjoys a solid base of support. The number of medical marijuana patients in the state has grown to an estimated 250,000, with 180 marijuana clubs or dispensaries in Los Angeles alone. Growers have settled into quasi-respectability, while certain doctors routinely authorize marijuana for their armies of patients. Dispensary owners claim the industry now provides $100 million in taxes to the state treasury. That’s a crucial point of leverage in a state facing a cataclysmic budget hole, and it was one of the strongest arguments for a bill, recently introduced in the state legislature, to legalize pot completely. The state’s hard-pressed governor last month signaled a willingness to consider that approach. “I think it’s time for debate,” said Gov. Arnold Schwarzenegger. “I think all of those ideas of creating extra revenues—I’m always for an open debate on it.”