(Reuters Health) - People who buy medical marijuana online may not necessarily get exactly what they expect when their package arrives in the mail, new research suggests.
Online, almost 70 percent of products made from cannabidiol – a marijuana plant extract also called CBD – had higher or lower concentrations of this drug than the label described, researchers report in JAMA. Too little or too much CBD can be unsafe or ineffective.
For the study, researchers searched online for medical marijuana products and bought 84 products marketed as containing CBD from 31 different companies.
Roughly one in five of the products also contained THC, the chemical in cannabis that makes gives people a high. Medical CBD shouldn’t contain THC, an ingredient that may be harmful to vulnerable patients including children and infants who use medical marijuana, said lead study author Marcel Bonn-Miller of the University of Pennsylvania Perelman School of Medicine in Philadelphia.
“CBD extracts are often used by people with seizures, anxiety, sleep problems, and autism, as well as pain and inflammation,” Bonn-Miller said by email.
Inaccurate labels on online CBD products “could lead to unwanted side effects from ingredients like THC, or missed therapeutic effects,” Bonn-Miller added.
Many products are expensive, and the study results suggest that some parents might be giving sick kids addictive drugs without knowing it, Bonn-Miller said.
The researchers tested each product to see how much CBD it contained and what other ingredients it had.
Overall, 36 products, or 43 percent, had more CBD than was indicated on the label and another 22 products, or 26 percent, promised more CBD than was actually included.
Another 26 items, or 31 percent, were considered accurately labeled; in these products, the CBD content was within 10 percent of the amount advertised on the packaging.
Some forms of CBD had more accurate labels than others, the study found.
Liquid versions used with vaping devices had inaccurate labels 88 percent of the time, while oils were mislabeled about 55 percent of the time.
There was THC in 18 of the 84 samples tested, sometimes in concentrations high enough to make patients intoxicated or impaired, especially if used by children, the researchers note.
The study wasn’t a controlled experiment designed to prove whether or how specific amounts of CBD or other ingredients might be helpful or harmful to patients using medical marijuana.
Still, the results suggest that patients should proceed with caution when shopping for medical marijuana products online, said Wayne Hall of the National Addiction Center at Kings College London and the Center for Youth Substance Abuse Research at the University of Queensland.
“Because the industry is still illegal under U.S. federal law, there has been very little oversight by the FDA and other bodies that are meant to protect consumer health,” Hall, who wasn’t involved in the study, said by email.
“The major problems that arise from not getting the dose on the pack is that you either do not take enough to get any medical benefit or you take more than you need and increase the risk of adverse side effects and also pay more than you need to,” Hall said.
Among other problems, too much cannabinoid can alter how the liver metabolizes medications, which might mean these medicinal marijuana products interfere with the effectiveness of other drugs people take, said Dr. Sachin Patel, a researcher at Vanderbilt University Medical Center in Nashville, Tennessee, who wasn’t involved in the study.
“Cannabidiol is being marketed for a variety of conditions from epilepsy to cancer without a solid scientific support, and in most cases without any support at all,” Patel said by email. “At this point it is buyer beware.”
SOURCE: bit.ly/2zDeMqO JAMA, online November 7, 2017.