CBD and THC content mislabelled in medical cannabis products

CBD and THC content in medical cannabis products often differs from what the labels claim, say those behind a new US study.

Researchers at the Massachusetts General Hospital (MGH) studied the urine of patients taking medical cannabis products.

Their findings, published in JAMA Network Open, show that the actual THC or CBD content is often different from what is expected.

The contents of these products can vary considerably from distributors’ claims, according to the study.

Researchers analysed urine samples from nearly 100 patients enrolled in a clinical trial of the effect of medical cannabis for anxiety, depression, pain or insomnia.

The results showed no CBD in around a third of the urine samples from patients who said they were using cannabis products that were CBD-dominant or had roughly equal parts CBD and THC.

THC was detected in almost 80 percent of samples, including among patients who thought they were only receiving CBD.

As more US states legalise cannabis sales, demand has increased but there is little consistency in product regulation or labelling.

Cannabis products containing THC are federally banned, but states have been passing laws legalising these products.

This has in turn led to a patchwork of laws that have varied impact on guaranteeing that consumers get what they expect. CBD does not come under FDA regulation.

“People are buying products they think are THC-free but in fact contain a significant amount of THC,” says Jodi M. Gilman, PhD, the paper’s lead author and an investigator in the Centre for Addiction Medicine in MGH’s Department of Psychiatry.

“One patient reported that she took a product she thought only contained CBD, and then when driving home that day she felt intoxicated, disoriented and very scared.”

Exactly how the cannabis was consumed mattered, too.

About 20 percent of patients who reported that they were vaping their medical cannabis had no detectable levels of THC or CBD metabolites in their urine samples.

This suggests that some vaping devices may not heat cannabis products sufficiently for patients to even inhale the active ingredients.

“A lot of questions about the content of the products and their effects remain,” says Gilman.

“Patients need more information about what’s in these products and what effects they can expect.”