Medical Marijuana Is a Trojan Horse That Pain Physicians Should Refuse to Accept

Forty-six percent of Americans want marijuana to be legalized. Seventy percent of Americans support the legalization of medical marijuana. The large gap between these 2 figures provides just enough wiggle room for politicians lacking in backbone to squeeze through and try to make everyone happy. The problem is that they are using physicians as a Trojan horse to do it--and pain physicians should be up in arms.

It's surprising to find this level of agreement on such a contentious topic; 46% of Americans don't agree that the sky is blue. Support for complete legalization has been slowly rising for years and may ultimately get to a majority (http://hcp.lv/ avgGfC). When does political backbone begin to form? The additional 30% of Americans who support medical marijuana are particularly well informed on the quality of clinical data on the subject. Instead, they are probably simply trying to be charitable to the sick, planning for their own old age and infirmity when they might want or need pain relief, or simply view marijuana as harmless enough that the risk-benefit ratio favors availability for those who are suffering. Still, others might want to be empowered to use marijuana as a reaction against their fear that their doctors aren't skilled enough and/or their medicines are not powerful enough to relieve pain, nausea, wasting, and other forms of suffering in advanced disease. Perhaps some are cynical enough to view medical marijuana as step one in a strategy moving toward legalization, but it is doubtful they're the majority.

If Americans want legal marijuana then it should be legal (as long as some of the revenue generated is targeted at improved substance-abuse treatment for those vulnerable individuals who might be harmed by this increased access). If, once marijuana is legal, there is a desire to develop special access programs for the medically ill, or even grow particularly pure or potent plants, so be it. Perhaps better safety and efficacy studies would follow. The present confusion between medical marijuana laws on a state level (which of course is not truly legal) and federal laws is the worst of both worlds (http://hcp.lv/aRce9q; http://hcp.lv/bBVksi).

Medical marijuana is a compromise that hurts the already troubled image of the pain doctor and threatens pain management (http:// hcp.lv/aUG0dF). Pain physicians are engaged in an ongoing struggle trying to keep already-legal, higher-quality medications (many of which are controlled substances) safe and available for people in pain. All this while the media paints the drugs as killers and the physicians as little more than dealers. Add to this the collateral credibility damage done by the cynical scams that arise around medical marijuana: A sudden epidemic of social phobia among college students and such; coached patients faking a variety of maladies to gain access to marijuana using a physician as the sympathetic gate keeper; etc. Often, such physicians are taking a political stance in such prescribing rather than a medically based one.

If marijuana were 100% legal, some doctors would still have qualms about its use in some of their chronic pain patients, in much the same way that they don't want their patients to smoke tobacco, overuse alcohol, overeat, and be sedentary (all of which are legal vices that nevertheless make it harder for patients to live a full and meaningful life with their chronic disease). Legalization wouldn't overcome the need for pain patients to strive toward a healthy lifestyle--an area in which many of them struggle. And even for those whose pain improves on medical marijuana, is that likely to help promote the other changes? However, medical marijuana does remove the specter of diversion that surrounds the obtaining of an illegal substance when one is being treated with a controlled substance that can be a commodity in such interactions (but not nearly enough to justify medicalization, in our view).

Indeed, some studies seem to show that marijuana provides only dubious benefits that at times throw the legitimacy of "medical marijuana" into question. As a sleep aid, marijuana has limited application because it disrupts the natural rapid eye movement sleep cycle (http://hcp.lv/cvZkjq); during withdrawal from marijuana, users may experience reduced sleep (http://hcp.lv/8Zzcue).

The primary difficulty in use of marijuana is its potential for abuse. When delivered via smoking, the dose can be titrated and provides nearly instant relief, but there are obvious problems with usage of smoking for prolonged treatment of an illness. As tetrahydrocannabinol (THC), the active ingredient, is not water soluble, oral formulations have their own share of difficulties. Ingested THC does not absorb well, takes one to two hours to take effect, and tends to produce more drowsiness and confusion--psychological side effects nonrecreational users do not seek.

In addition, there have been studies comparing THC and codeine to determine which has greater efficacy in respect to pain relief (http://hcp.lv/dg3ECS). This study by Noyes et al. concluded that marijuana's efficiency, at high doses, is comparable to high doses of codeine. However, there are strong psychological side effects that may limit THC's viability as a pain reliever, while codeine causes much less mental clouding and does not impair users to the extent that marijuana use does. The NIH 1997 workshop on the medical utility of marijuana concluded that, "Since the approval of dronabinol in the mid- 1980s for the relief of nausea and vomiting associated with cancer chemotherapy, more effective antiemetics have been developed, such as ondansetron, granisetron, and dolasetron, each combined with dexamethasone. The relative efficacy of cannabinoids versus these newer antiemetics has not been evaluated. Smoked marijuana was tested in one trial in patients who previously had no benefit from older antiemetic agents. Nearly one-quarter of patients who initially agreed to participate later declined, citing bias against smoking, the harshness of smoke, and preference for dronabinol. Among the remaining 56 patients, 78% rated smoked marijuana very effective or moderately effective. Sedation was seen in 88% and dry mouth in 77%. It is not known whether smoked marijuana would benefit patients' refractory to the current generation of antiemetic therapy" (http://hcp.lv/9kqERr).

Marijuana's proponents frequently cite "appetite stimulation" as one of its redeeming qualities, and it does appear to help combat AIDS-related wasting. In one study, small doses of dronabinol were reported to be effective in appetite stimulation without confounding mental acuity, while high doses of dronabinol (10 mg 4x daily) appeared correlated to compromised acuity. However, the weight gained was not lean body mass, indicating that marijuana's use as an appetite stimulant may be limited (http://hcp.lv/dB2qmj).

Indeed, marijuana seems to be neither a panacea nor a deadly toxin. A recent population-based- case-control study seems to indicate no increased risk of lung cancer and a possible mild protective effect (http://hcp.lv/cuQIqR), although there appears to be a possible synergistic effect between tobacco and marijuana use in the form of increased risk for lung cancer as compared to smokers of only tobacco (http://hcp.lv/9kqERr). The data supporting medical marijuana are too weak to offset the other potential damage to pain management.

Legalize it first, medicalize it second.

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Steven D. Passik, PhD, is a clinical psychologist at Memorial Sloan-Kettering Cancer Center, New York, New York. He specializes in the psychological aspects of cancer, including palliative care and symptom management, with an emphasis on pain, depression, nausea, and fatigue. Passik is a consultant and speaker for Cephalon, Purdue, King, and PriCara.

Sharang Tickoo is a biology major at Occidental College in California.