USA Today 27 July 2014
Doctors say they’re increasingly fielding questions about the safety of marijuana, as use of the drug rises and more communities consider legalizing it. Colorado and Washington state have legalized recreational marijuana, and medical use is allowed in 21 states and Washington, D.C.
USA TODAY’s Liz Szabo talked to experts about what scientists know and don’t know about marijuana’s risks and benefits.
Q. How common is marijuana use?
A. About 12% of people of Americans over age 12 have used it in the past year, according to the Substance Abuse and Mental Health Services Administration.
Use of marijuana among high school students has been increasing since the 1990s. If current trends continue, marijuana use among high school seniors could soon become more common than cigarette smoking, says Nora Volkow, director of the National Institute on Drug Abuse.
Q. Is marijuana addictive?
A. Sometimes. About 9% of those who experiment with marijuana overall — and nearly 17% of those who use it as teenagers — will become addicted, according to the definition of addiction used in the Diagnostic and Statistical Manual of Mental Disorders, Volkow says. Up to half of people who smoke marijuana daily become addicted.
According to the 2012 National Survey on Drug Use and Health, 2.7 million people over age 12 meet criteria for addiction to marijuana.
Q. What are the potential medical uses of marijuana?
A. Smoking marijuana may stimulate appetite, especially in patients with AIDS, according to an Institute of Medicine report.
Smoking pot also may alleviate the nausea and vomiting caused by chemotherapy treatments for cancer. It also may relieve severe pain and spasticity, when muscles become overly tight and rigid. Marijuana also could potentially help treat glaucoma, by decreasing pressure in the eye.
But marijuana also may make the cognitive problems associated with HIV even worse, according to a 2004 study.
“If an individual comes in with severe pain and I haven’t been able to manage it with any other means, I am willing to consider it, but with a lot of precaution,” says Steven Wright, a pain and addiction medicine specialist in Denver. “But unless you are really severely affected by pain, it’s not in your favor in the long term.”
Q. Is medical marijuana approved for use by the Food and Drug Administration?
A. No. But the FDA has approved two drugs made with cannabinoids – active ingredients in marijuana – called dronabinol and nabilone. Both are approved to treat chemotherapy-related nausea and vomiting in patients who aren’t helped by other therapies.
The FDA is reviewing an unapproved drug, called Sativex, to treat multiple sclerosis. It’s already approved in Canada, the United Kingdom and other countries. And researchers are testing an experimental drug called Epidiolex to treat childhood epilepsy.