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February 19, 2015

The medicinal use of marijuana: “We need more data,” panel says

Cannabis leafAlthough legalization of medical marijuana in Pennsylvania may be inevitable, more study of the medicinal use of cannabis is needed, said a panel of psychiatry faculty members during a clinical grand rounds, “Marijuana Demystified,” at Western Psychiatric Institute and Clinic Feb. 6.

“We’re going to talk science, not ideology; we’re going to talk evidence-based … what we know, what we do not know and what needs to be studied,” said Antoine Douaihy. “There is so much of that debate that is not based on scientific opinion.” He labeled Pew Research Center surveys showing increasing numbers of Americans accepting the idea of legal marijuana use “interesting, disturbing, challenging.”

Added John Rozel: “The professional and scientific consensus at this point in just about every medical organization, is: ‘We need more data.’”

“‘Medical marijuana’ is not a term endorsed by any medical society,” said Julie Kmiec. “It is a political term.”

Families of pediatric epilepsy patients whose frequent seizures are uncontrolled by current medications have been protesting in Harrisburg, she noted, promoting the legalization of cannabidiol, a non-intoxicating ingredient in marijuana that can have medical benefits for such children.

“There are some medical benefits” of marijuana, Kmiec allowed. It has been shown to alleviate nausea and vomiting as a side effect of chemotherapy and help with AIDS wasting syndrome. It also may decrease spasticity in multiple sclerosis patients, cancer pain, rheumatoid arthritis symptoms and neurotropic pain.

But there also are known harms, usually from chronic use of marijuana, she said. Nine percent of marijuana users become addicted, and marijuana users more often move on to stronger illicit drugs, findings she acknowledged were sometimes disputed but which have been confirmed via studies of twins.

Some marijuana users also show “diminished lifetime achievement,” from career progress to relationship satisfaction, she noted, as well as increased numbers of motor vehicle accidents and performance impairment among pilots tested in flight simulators, even 24 hours after smoking.

Those who use marijuana also are more likely to have symptoms of everything from bronchitis to psychosis and, among those who have not yet exhibited symptoms of schizophrenia, pot use can cause the disease to manifest earlier. Other documented effects in users can include a decline of 6 points in IQ; development of anxiety or depression; acute cardiac events, including a 3.4 percent increase in heart attacks; the increased risk of periodontal disease and, for those with hepatitis C, liver fibrosis.

California was the first state to legalize medical marijuana in 1996 for AIDS, cancer pain and “any other illness for which marijuana provides relief.” Since then, New York has approved it with more stringent parameters for such “debilitating or life-threatening conditions” as AIDS, cancer, amyotrophic lateral sclerosis, Parkinson’s and multiple sclerosis, although it left room for the list to be expanded by legislation.

A 2011 study of 2006 pot clinic visits in California found that most patients claimed to need marijuana for pain; at the bottom of the list were requests for relief of seizures and itching. Slightly more than half the patients were using it as a substitute for other prescriptions. The same survey found physicians prescribing it most often for back, spine and neck pain, as well as sleep disorders, and least often for eating disorders. Patients on average were 41, white and male, and 67 percent were using the drug daily, via smoking.

When marijuana is no longer considered an illicit drug by society, and sometimes “packaged like candy,” Kmiec asked, will that increase its recreational use? A University of Michigan survey of changing attitudes among high schoolers has been charting pot’s perceived danger and frequency of use since 1975. It found that, following First Lady Nancy Reagan’s 1980s “Just Say No” campaign, there was a reduction in use and an increase in perception of marijuana’s dangers. Following President Bill Clinton’s admission that he smoked pot but “didn’t inhale,” “That’s when things began going downhill for us,” Kmiec said — pot’s public image improved, and its use increased.

Today, she said, more kids use alcohol than marijuana but more go into treatment for marijuana addiction.

medical marijuana prescription


Kmiec concluded that physicians should ask themselves: “Would you be confident prescribing a drug with no dose, no dosing schedule. …”

If this were any other substance, she added, would people be trying to circumvent the FDA approval process?

While there is strong evidence of “adverse neurodevelopment effects on adolescents,” noted Rozel, “criminalization of marijuana in the U.S. is doing significant harm.”

The United States spent $3.6 billion on marijuana arrests in 2010, for instance, and today there are six times more arrests for pot among black men than white. Rozel also decried the “collateral consequences of conviction” — 111 laws preventing those with pot convictions from doing everything from acquiring student loans to becoming a professional wrestling promoter. By comparison, there are only 59 things convicted sex offenders are legally prohibited from doing. “I would suggest that is not equitable.”

Since Philadelphia decriminalized small amounts of marijuana possession last year, it saw a 78 percent drop in marijuana arrests “almost immediately,” he noted.

Bills to make medical marijuana legal in Pennsylvania passed a legislative committee and the Senate last year but the House did not vote on it, and then-Gov. Tom Corbett said he would not have signed it.

Already in the 2015 session, Senate Bill 3 and House Bill 193 to legalize some medical uses of pot in edible form have been introduced. Gov. Tom Wolf supports the idea. The proposed law includes a state board of regulation and a state lab to police marijuana potency. Much of the money earned through the bill would be funneled into research.

But Rozel cautioned that marijuana in edible form, such as in baked brownies, can deliver higher doses in a shorter time and pose a greater risk for small children who might get their hands on the drug in this disguised and more attractive form.

Besides potentially aiding with the symptoms of illnesses, medical marijuana would present new opportunities for small businesses in the state, which may increase its support. Rozel also noted that software companies are providing much of the money being used to lobby for such legislation, since they would be able to sell computer programs needed for the state’s medical marijuana user registry.

But, besides marijuana’s documented negative effects, it also poses legal and other new societal questions: Which state office will oversee medical marijuana: the Liquor Control Board, Department of Health or some other agency? Will there be a need for increased DUI testing? Will banks be legally able to handle the funds from marijuana businesses? How will landlords and hiring departments view such marijuana use? Will health care professionals understand other drug interactions with marijuana? Will health care facilities want to order marijuana for inpatients?

“Medical marijuana is probably coming,” he said, “whether we like it or not, whether there’s going to be that evidence in a timely manner.

“Let go of your need to see medical marijuana as a good, evidence-based medicine or social policy … look for the research opportunities.”

Till now, research on marijuana’s effects has been difficult, since the FDA has restricted it along with other illegal drugs.

“I do not buy into this ‘radical acceptance,’” responded Douaihy. “It is a big, big cultural issue.” When looking at the diseases for which medical marijuana use has been legalized in several states, he said, “It’s a bizarre list. Who came up with this? There is no scientist who came up with this list.

“We don’t even know the ingredients” of various medical marijuana brands, he said. “You go to one of those places that dispenses — we don’t even know the potency.” Plus, he said, the degree of danger depends heavily on the profile of the user — young or old, infrequent or heavy smoker.

“Just because we have made mistakes in the past” with societal rules about cigarettes and alcohol, Kmiec said, “doesn’t mean we have to move forward and make more mistakes.”

Concluded Douaihy: “I will never stop advocating against the misinformation.”

—Marty Levine