Does the Pot Pill Work?

"Medical marijuana," the U.S. Drug Enforcement Administration says, "already exists."

They don't just mean in California. A pill known as Marinol has been legal and approved by the Food and Drug Administration for use with a prescription anywhere in America since 1985.

It's active ingredient? Dronabinol, better known as THC, the primary psychoactive element of the cannabis plant.

"Marinol provides standardized THC concentrations, does not contain the other 400 uncharacterized substances found in smoked marijuana, such as carcinogens or fungal spores, and is not associated with the quick high of smoked marijuana," said Neil Hirsch, a spokesman for Marinol manufacturer Solvay Pharmaceuticals.

But Marinol is not the same thing as traditional, smokable marijuana. It is a less complex substance lacking both some of the good components found in traditional marijuana (such as cannabidiol, which has been found to have anti-seizure effects) and the bad or not-yet-fully-understood components (among them potential carcinogens) that can also come with the drug.

Ken Trainer, a 60-year-old Massachusetts resident who has battled Multiple Sclerosis for 25 years, said he has long been smoking marijuana to deal with the regular tremors he gets in his arms and legs.

"If I smoke a joint, the tremors go away most times before the joint is gone," he said. "It makes my life a little easier." Marinol, by contrast, "didn't really do much of anything for me," he said.

56-year-old Des Moines resident Jeff Elton, who was diagnosed with gastroparesis six years ago, had a similar experience when he was prescribed Marinol to deal with his chronic nausea and vomiting.

"I felt no relief, I didn't feel ill, I felt nothing," he said. "It might as well be M&M's."

Elton said he switched to marijuana, which he smokes through a vaporizer - a device that heats the active ingredients into a vapor instead of burning them. He said it allows him to keep down his food and regain some of the weight he lost while on Marinol.

"[One] problem with Marinol is that it's orally administered," Dr. Mitch Earleywine, an associate professor of Clinical Psychology at the State University of New York at Albany, said in an email. "Therefore, it takes longer to work than cannabis inhaled from a vaporizer. (Usually 90 minutes at best rather than 15 seconds - a meaningful amount of time to the nauseated.)"

"It's harder to control dosage, too, so folks end up discombobulated or without symptom relief," he added. "In addition, folks who are vomiting can't hold down the pills." Earleywine also said that a dose Marinol costs three to five times as much as a comparable dose of medical marijuana.

Defenders note that Marinol is not meant to be a cure-all: It has been approved specifically for treating nausea and vomiting associated with cancer chemotherapy and for treating anorexia associated with weight loss in patients with AIDS.

"When the whole push for the smoked product came along, it was often for those two indications," said Dr. Herbert Kleber, a professor of Psychiatry at Columbia University and the former deputy drug czar under President George H.W. Bush. "And in general, I've not seen any need for the smoked form of marijuana for those two indications. Marinol had already been shown to be quite effective for those two things."

"Are there actions in the whole plant that you don't get from just the Marinol? I would be surprised if there wasn't," he continued. "The problem is that most of the data about the potential medical actions of the smoked form are anecdotal."

Research into the effects of medical marijuana is ongoing: The University of California, San Diego, for example, boasts a Center for Medicinal Cannabis Research engaged in "focused controlled clinical trials on the efficacy of cannabis in patients diagnosed with HIV/AIDS, cancer, seizures or muscle spasms associated with a chronic debilitating condition, or any other serious condition providing sufficient theoretical justification." (The director of the UCSD program, Dr. Igor Grant, was out of the country and could not be reached for this story.)

The Los Angeles Times, which offers a nice overview of the current research, writes that "a growing body of research supports [medical marijuana's] medical usage, but some of it is cautionary." Marijuana has been found to be effective in counteracting severe pain, nausea and loss of appetite, though questions remain about the drawbacks, among them possible respiratory damage and increased cancer risk.

Dr. Kleber, who said he has prescribed Marinol to a patient and found it to be effective, points to what he characterizes as a significant advantage of the pill over traditional marijuana: "People don't abuse it."

"Marijuana addiction is becoming common and as a result I'm seeing an increasing number of people who have trouble stopping marijuana," he said. "Contrary to popular beliefs that there is no marijuana withdrawal, there is marijuana withdrawal. It's very clear cut."

The calculus, then, isn't quite as simple as the Drug Enforcement Administration suggests: Marinol and medical marijuana may share an active ingredient, but they offer somewhat different benefits and different drawbacks. Proponents of medicinal marijuana say it's disingenuous to hold up Marinol as a direct alternative to the more traditional form of the plant.

"I just don't understand how they won't let me smoke a joint, but they're more than happy to write me out prescriptions for anything that I want," Trainer said.