Kate Johnson

October 29, 2012

MONTREAL, Canada — Physicians who legally use medical marijuana to treat their own debilitating conditions such as chronic pain or nausea are considered unsafe to practice medicine in the state of Colorado until such time that they no longer need the treatment, according to a policy from the Colorado Physician Health Program.

"We took a conservative stance," Doris Gundersen, MD, Medical Director of the Colorado Physician Health Program, told Medscape Medical News after her presentation here at the International Conference on Physician Health (ICPH). "We don't want to deny them treatment...but until they no longer need it, or we have better ways of correlating impairment, they can't practice."

She said Colorado is the first state to come up with such a policy, prompted by reports of physicians who were legally using the substance. "The medical board appealed to us about how to manage this, there were several physicians referred and we happened to see they were also using marijuana — they had legitimate [Medical Marijuana Registry identification] cards," she said.

"This is where we got a little nervous. All of the associate medical directors at the Colorado Physician Health Program are psychiatrists and addiction specialists, and we recognized very quickly that this may not be compatible with practicing medicine safely.... We don't want physicians excluded from treatment that they need, but at the same time we need to protect the public," Dr. Gundersen said.

"Viral Situation"

In her presentation at the conference, Dr. Gundersen told delegates about the "viral situation" in Colorado, where the number of Medical Marijuana Registry identification cards has "grown exponentially" from around 17,000 in 2009 to almost 128,000 by June 2011.

"According to the Denver Post, there are more medical marijuana dispensaries in Denver than there are Starbucks and liquor stores combined," she said.

While debate continues about the general safety and efficacy of medical marijuana, physician use of this treatment deserves specific attention, she emphasized.

"The way we view it is that physicians, like pilots, are in safety-sensitive employment.... There's not a good way to measure concentrations and correlate that to impairment, but very low concentrations can impair," she said, citing one study suggesting that among airline pilots, impairment on flight simulators persisted up to 24 hours after smoking a marijuana cigarette, even though subjects were unaware of it (Am J Psych. 1985;142:1325-1329).

Another study showed decision-making errors 50% to 70% of the time in long-time marijuana users compared with 8% of the time in nonusers (Neurology. 2006;66:737-739).

It's unclear what the cut-off level is for marijuana impairment. "Even at levels as low as 3 ng/mL there are some mind-altering effects," she said, adding that a concentration of at least 10 ng/mL is required to relieve symptoms such as chronic pain or nausea.

Public Safety "Supersedes" Individual Rights

"To have a license to practice is a privilege, not a right, and public safety supersedes an individual physician," she said. "If we get more sophisticated in correlating levels with safety, our policy may change, but right now it's conservative and it's honestly to protect the public but also the physician from making errors."

Dr. Gundersen pointed out that physicians also should not practice while impaired by other medications or alcohol, although the use of these substances does not preclude them from practicing medicine altogether.

"Things that are approved by the FDA generally have pretty standardized dosing, and we can perform some neuropsychiatric testing to make sure physicians are not impaired," she explained. "Again, with alcohol we have better cut-offs in terms of what should be considered impairing."

Dr. Gundersen said the marijuana policy is a "first effort out there to make sense of something we don't have enough science about to make decisions on, and so far there's been no case law challenging it."

Asked to comment on the policy, Andrew Clarke, MD, Executive Director of the Physician Health Program of British Columbia, told Medscape Medical News it is "not an unreasonable position — whether or not it's the best position is an ongoing debate.

"There are many medications that impair one's judgment and people do take them, so it's a tough call to decide when would we draw a line and say anybody taking this medication shouldn't be practicing," he said in an interview. "Or maybe there are circumstances when someone who uses that medication from time to time might still be able to practice in-between the times they use it, like alcohol or other sedative medications, or sedating antihistamines."

A pivotal point in the debate is the issue of self-prescription, said Dr. Clarke.

"It's clear that nobody should be self-prescribing marijuana ever," he said. "There's lots of medications out there that impair one's judgment and physicians use those medications to get better, but it's very important that it be done under the supervision of someone else.

"When we're in a situation where there's an illness that impairs judgment or we're prescribing a medication that impairs judgment and there's no second opinion on that, then we have a very potentially difficult situation," Dr. Clarke said.

Dr. Gundersen and Dr. Clarke have disclosed no relevant financial relationships.

2012 AMA-CMA-BMA International Conference on Physician Health (ICPH) Presented October 27, 2012.