The new Institute of Medicine (IOM) report on medical marijuana, "Marijuana and Medicine: Assessing the Science Base," is not a rejection of medical marijuana use, as some anti-drug groups claim. Nor is it a total repudiation of current government policy, as certain policy reformers would have you believe. What it is is perhaps the most level-headed government report on the subject of illicit drugs to emerge in the last decade.
Commissioned by the Office of National Drug Control Policy (ONDCP) -- a steadfast opponent both of marijuana decriminalization and medicinal use of smoked marijuana -- the report by the independent IOM largely steers clear of rhetoric and propaganda. "It's a remarkably sane and reasoned take on the marijuana issue, and nicely free of hysteria -- both the report and the initial reactions to it," said Gregory Dixon, executive director of the Center for Professional Health at Vanderbilt University, and former deputy director of the national Fighting Back prevention initiative.
Charged primarily with assessing the science surrounding the benefits and risks of medical use of marijuana, the IOM panel that conducted the study reviewed published research and gathered input through hearings and site visits to cannabis buyers' clubs and AIDS clinics. As a result of the 18-month study, the report concluded that there is a "substantial consensus" among researchers that cannabinoids -- the active ingredients in marijuana -- have a natural role in pain modulation, control of movement, and memory, and may have therapeutic value.
More research is needed, however, especially into how the various cannabinoids (including THC) work, the report said. "Marijuana has potential as a medicine, but it is undermined by the fact that patients must inhale harmful smoke," said report co-leader Stanley Watson from the Mental Health Research Institute at the University of Michigan. "Until researchers develop a safe and effective delivery system, caregivers must consider the health problems that result from smoking when deciding whether to recommend marijuana to patients."
That's a far cry from the claims of groups like the Family Research Council, which issued a press release saying the IOM report "rejected the theory that marijuana is a medicine, citing its negative health consequences." Nor, however, does the report actually "come close to saying that everything the federal government has been claiming about marijuana for the last 50 years is wrong," as a release from the group AIDS Action stated.
In fact, researchers concluded that the brain does develop tolerance to cannabinoids and dependence can occur, which runs against the beliefs of pro-pot advocates. But, "reefer madness" claims to the contrary, the study also found that withdrawal symptoms are mild and short-lived compared to drugs such as opiates or benzodiazepines. The effects of cannabinoids on the immune system -- long cited as a potential downside of marijuana use -- are also unclear, the report added.
A Limited, Qualified Endorsement
While hardly a ringing endorsement of medical use, the IOM report agrees that research shows that marijuana has promise as a medicine. Cannabinoids "would be moderately well-suited for certain conditions, such as chemotherapy-induced nausea and vomiting and AIDS wasting," the report said. The IOM panel notes that patients report fewer negative side-effects -- such as unpleasant psychological feelings and disorientation -- from smoked marijuana than from taking Marinol, or oral THC, and that the smoked drug is faster-acting. On the other hand, the report said that research does not support use of marijuana for treating glaucoma, Parkinson's disease or Huntington's disease, as some patients and advocates claim.
Researchers also found that the broad range of effects from marijuana use, including reduced anxiety, pain, nausea and increased appetite, may be beneficial for certain patients (such as those grappling with AIDS wasting syndrome) while undesirable for others. The study recommends further study of the psychological role of cannabinoids.
Assessing the Risks
Medical use of marijuana is not without risk, the report noted. The primary negative effect would be diminished psychomotor performance, and a minority of users experience dysphoria, or unpleasant psychological feelings. The impact of short-term use on the immune system is "not well-established, but if they exist, are not likely to be great enough to preclude a legitimate medical use," the report added.
More worrisome to researchers is long-term use of smoked marijuana, which may increase the risk of cancer and complications during pregnancy. Research is lacking, however, and the report recommends conducting more. The panel said that clinical trials of smoked marijuana should be of short duration (six months or less) to limit harmful side-effects, and not be directed at developing marijuana as a licensed drug but rather as a first step toward developing non-smoked medications (administered through inhalers, for example).
"However, it will likely be many years before a safe and effective cannabinoid delivery system, such as an inhaler, will be available for patients," the IOM panel noted. "In the meantime, there are patients with debilitating symptoms for whom smoked marijuana might provide relief."
"The use of smoked marijuana for those patients should weigh both the expected efficacy of marijuana and ethical issued in patient care, including providing information about the known and suspected risks of smoked marijuana use," the report continued. Smoked marijuana should only be used if all approved medications fail to provide relief, the study said. "Until a non-smoked, rapid-onset cannabinoid drug delivery system becomes available, we acknowledge that there is no clear alternative for people suffering from chronic conditions that might be relieved by smoking marijuana, such as pain or AIDS wasting," according to IOM.
So how does that square with the assertion that "the study concludes that these is little future in smoked marijuana as a medically approved medication," as ONDCP has been emphasizing? As drug czar Barry McCaffrey has been telling reporters (and the report itself notes), it may be a decade or more before cannabinoid drugs are approved by the FDA -- assuming that pharmaceutical firms are willing to invest the hundreds of millions of dollars required for research and development. If the federal government plans to live up to its pledge to base its medical marijuana policy on science, it will have to take IOM's "interim solutions" to heart -- meaning some degree of acceptance of smoked medical marijuana use until such time in the future that cannabinoid drugs are developed and brought to market.
So far, however, there is little indication that the IOM report will lead to immediate policy changes. McCaffrey said this week that medical use of marijuana would remain illegal, even in those states that have passed medical marijuana referenda. Meanwhile, medical marijuana advocates are calling for the drug to be reclassified from Schedule I of the federal Controlled Substances Act (the category for drugs with high abuse potential and no medical use) to Schedule II (which includes drugs that have both abuse potential and legitimate medical uses).
The Gateway Theory
Finally, the report tackles the thorny question of whether research shows that marijuana is a "gateway" to other drug use. The report said that because use of marijuana, alcohol and tobacco is so widespread, use of these drugs typically precedes other drug use, and so is a "gateway" in that sense. But the report states, "These is no conclusive evidence that the drug effects of marijuana are causally linked to the subsequent abuse of other illicit drugs."
Although not directly relevant to the medical marijuana issue, this finding may have the most profound impact on the policy debate, since the gateway theory has been one of the cornerstones of federal policy against marijuana use. In its own statement of the study, ONDCP made a negative assessment of this finding, writing, "The study asserts that progression from marijuana to other drugs arises not from pharmacological properties of marijuana itself but because marijuana serves as a gateway to the world of illegal drugs in which youths have greater opportunity and are under greater social pressure to try other illegal drugs." In fact, ONDCP's statement goes several steps beyond what the IOM report actually says.
"The findings disputing the gateway theory are certainly cause for pause," says John Hulick, public policy director for NCADD of NJ, who notes: "If we want to live by the research, we have to die by the research."
Concerns Among Preventionists
Richard McCain, executive director of the Substance Abuse Initiative of Greater Cleveland, voiced the concerns of many when he told Join Together that he worries that allowing medical use of marijuana could make preventionists' job more difficult and lead to increased recreational use. But the IOM report says that there is no convincing data to support claims that medical use will lead to increased use in the general population. "The existing data are consistent with the idea that this would not be a problem if the medical use of marijuana were as closely regulated as other medications with abuse potential," the IOM report said.
Still, McCain says that the decidedly mixed results of the IOM report raises the question of whether it's worth taking the risk. "One of the things that concerns me is how beneficial it really is compared to the negative message we send to young people," he said. "From my standpoint, I don't think the benefits outweigh the negatives."
Because the IOM examines both aspects without coming down firmly on one side or the other, it may not sway the opinion of people like Don Griffin, program manager of the Community Prevention Partnership in Martinsburg, W.Va., who says, "I think that medical use and the exploitation of that is mostly bogus." Griffin shares McCain's concern about the effect legalizing medical marijuana could have on prevention. But he also worries that allowing pharmaceutical firms to gain control of marijuana to expand and exploit its medical potential could bring its own problems, including more pot growers and illegal diversion via organized crime. "I'm skeptical of where such a report will take us," he tells Join Together.
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