Edible Marijuana Labels Often Have Potency Wrong, Study Says

 In Edibles, National News, Plant Science

An analysis of 75 edible marijuana products sold to patients in Seattle, San Francisco and Los Angeles found that labels on just 17 percent accurately described their levels of THC, the main psychoactive ingredient, researchers reported Tuesday.

Sixty percent of the products had less THC than their packages advertised, and 23 percent of them had more THC than claimed.

“We need a more accurate picture of what’s being offered to patients,” said Dr. Donald Abrams, the chief of hematology and oncology at San Francisco General Hospital. He was not involved in the new study, which was published in JAMA.

“What we have now in this country is an unregulated medical marijuana industry, due to conflicts between state and federal laws,” Dr. Abrams said.

After ingesting marijuana, patients experience the maximal high one to three hours later. (It is felt within minutes after smoking.) Inaccurate labels complicate the consumption of marijuana for medical purposes.

Products with too little THC, or tetrahydrocannabinol, may fail to deliver symptom relief to those with debilitating conditions like chronic pain, and those with too much may overwhelm users.

Some of Dr. Abrams’s older cancer patients have tried edibles, he said, because they do not want to smoke marijuana. But some have eaten too much THC, with unpleasant results such as severe anxiety.

Read more at nytimes.com