Medical Marijuana: Smoke & Mirrors?

In January, New Jersey became the 14th state in the nation to legalize marijuana use for certain chronic illnesses. Other states where the use of medical marijuana is permitted include Alaska, California, Colorado, Hawaii, Maine, Michigan, Montana, Nevada, New Mexico, Oregon, Rhode Island, Vermont, and Washington; around a dozen more states are weighing pending bills. The New Jersey law is the most restrictive in the nation and authorizes prescribed marijuana for only a handful of chronic illnesses, such as multiple sclerosis, cancer, glaucoma, epilepsy, Crohn's disease, AIDS, muscular dystrophy and Lou Gehrig's disease. Unlike other states, physicians in New Jersey will not be able to prescribe medical marijuana for anxiety, headaches, or chronic pain.

The state plans to authorize 6 dispensaries, and patients will receive identification cards authorizing them to purchase the drug. They will not be able to grow their own marijuana or use it in public, however. And individuals without a prescription will still be subject to criminal prosecution if caught in possession of marijuana.

Richard J. Rosenbluth, MD, is medical director of the Hospice Program and division chief of Geriatric Oncology at John Theurer Cancer Center at Hackensack University Medical Center in New Jersey. He is also the editor of the Journal of Pain Management, and he supports New Jersey's decision to legalize marijuana for medical use, predicated on a physician's determination that good clinical evidence exists to prescribe it. "I believe any drug that might be beneficial should be decriminalized, if currently not available," he said. "Marijuana should be available and doctors should treat it as any other drug, as per the Medical Board of California's 2004 recommendations," said Rosenbluth.

Shifting attitudes toward medical marijuana

According to Patrick Stack and Claire Suddath, authors of "A Brief History of Medical Marijuana," published in Time, medicinal marijuana can be traced back to Emperor Shen Neng of China, who prescribed marijuana tea in 2737 BCE as a treatment for gout, rheumatism, malaria, and poor memory. Its use became widespread throughout Asia and the Middle East. As of the late 18th century, medical journals in Britain and the United States were recommending hemp seeds for everything from inflamed skin to incontinence and venereal disease. Marijuana for medical use eventually fell out of favor in the United States, however, as state and federal regulators imposed increasingly harsh criminal penalties for growing, possessing, using, and selling marijuana.

Paul M. Zeltzer, MD, clinical professor in neurosurgery, David Geffen School of Medicine, University of California Los Angeles, explained that medical marijuana has been tainted with an association between marijuana and criminal enterprise. "Smoking medical, ordinary marijuana helps to alleviate many symptoms of pain and depression in persons who have cancer," he said, but he noted that marijuana use has been commingled with "an underground that involves crime syndicates and domestic/foreign nationals who may kill and maim in the process of cultivation, acquisition, and distribution." Some people have had trouble divorcing these two issues. "One alternative," Zeltzer suggests, "would be for [marijuana] to be [completely] legalized, thus sidestepping or eliminating the crime connection and adding to our country's tax base."

Although a minority of Americans support legalizing marijuana outright, 81% do support legalizing marijuana for medical purposes, according to an ABC News/Washington Post poll. Presidential administrations have differed on what approach to take toward medical marijuana, which remains a federal crime. Under the Obama administration, the Justice Department formally announced that it will not prosecute people who are using marijuana in compliance with state laws that permit its use for medicinal purposes. This is a reversal of the position taken by the previous administration, which dispatched federal agents to raid marijuana dispensaries and farms in states with legalized medical marijuana. Operators were charged under federal drug laws.

The FDA maintains that "marijuana has a high potential for abuse, has no currently accepted medical use in treatment in the United States, and has a lack of accepted safety for use under medical supervision." Though the FDA bans the use of raw marijuana, delta-9-tetrahydrocannabinol (THC) is the herb's most active ingredient and has been available by prescription as dronabinol (Marinol) since 1985. It is sometimes used to treat chemotherapy-induced nausea and vomiting. Rosenbluth said in terms of patient benefit, research fails to show either dronabinol or raw marijuana as superior to one another. He added that "anecdotally, patients who have prior history of smoking marijuana seem to get more benefit from smoking than from oral preparations." The NCI advocates THC use only when first-line therapies prove ineffective.

How does medical marijuana affect patients?

Despite marijuana being available for centuries, years of study have failed to elucidate its curative and palliative properties. Some studies have provided pretty strong evidence that marijuana reduces nausea and improves appetite in patients on chemotherapy. It also relieves aching and numbness in patients with AIDS and may alleviate some neurological problems associated with multiple sclerosis.

In patients with cancer, Rosenbluth said, "Several benefits have been attributed to marijuana, including improvement in anorexia/cachexia (cancer wasting syndrome), anti-nausea [properties], and help with depression and anxiety." Rosenbluth said there have not yet been any good clinical trials that confirm these benefits, however. "What trials do exist have generally not used smoked marijuana-only dronabinol." Rosenbluth said he is not convinced that marijuana is superior to other approved agents and suggested it may be significantly less effective than many of them.

Adverse effects associated with marijuana use are few and manageable, Rosenbluth said. "They include dysphoria, depersonalization syndromes, drowsiness, dizziness, and mild cardiac and circulatory side effects. These effects may be less apparent in younger patients and more so in the elderly."

Can marijuana slow tumor growth?

"There is a good deal of interest in some basic laboratory research indicating anti-tumor effects of cannabinoids," Rosenbluth said. Some researchers are experimenting with THC to reduce tumor growth. These studies are all in their early phases, but Rosenbluth said preliminary findings are interesting, and he hopes relaxation of medical marijuana laws will allow "cannabis and its components to be studied freely throughout the country, as any other potentially beneficial drug."

Despite the Obama administration's relaxation on prosecutions, many researchers are still having difficulty getting approval to conduct studies that involve smoking marijuana. Requests to conduct the studies must go through the National Institute on Drug Abuse (NIDA), which controls supply from a plantation at the University of Mississippi, the only federally approved source of marijuana. NIDA routinely turns down study requests unless they are designed to evaluate the potential harm from smoking marijuana. The Drug Enforcement Agency has also declined petitions from researchers requesting permission to grow their own marijuana for use in studies.

The thorny side of medical marijuana

Legalizing medical marijuana has not been without problems. Law enforcement officials in states where it is legalized complain that many healthy people take advantage of the law to procure marijuana and that growers are spreading from rural areas into the city. The city of San Jose, California, which has as many as 30 dispensaries operating within the city limits, recently announced it would be forcing all dispensaries to close. Related crime has also been a concern, and several states and municipalities are tightening regulations on marijuana dispensaries.

Most states with medical marijuana laws allow employers to refuse employment to individuals who use medical marijuana. In some states, like Colorado, the laws are ambiguous and employers are unclear as to whether they can forbid employees to use medical marijuana outside of work. Schools are also grappling with the issue, as well, with more high school students-particularly in areas with less restrictive medical marijuana laws-receiving prescriptions for marijuana, increasingly to treat ADHD. In addition, some facilities that perform organ transplants acknowledge denying transplants to patients who use medical marijuana.

In the absence of any proven benefits from smoking marijuana, physicians in the 14 states where it is legal may want to discuss some of the pros and cons with their patients prior to issuing a prescription. Patients need to be aware of the potential impact of medical marijuana on all facets of life and should be wary of letting the anecdotal hype surrounding medical marijuana use dissuade them from first trying a proven treatment option.

See our companion article, "Medical Marijuana: An Oncologist's Perspective."