And all three cannabis chemicals, but especially CBD, inhibited two of the primary UGT enzymes in the liver.
CBD was also found to block three enzymes that account for about 95% of UGT metabolism in the kidney, which helps clear toxins and some drugs from the body.
CBD, THC block enzymes that break down other meds
“It’s a very, very good reminder that these interactions are real,” Bednarczyk says. “It’s important for physicians and pharmacists who are working with patients to explore this.”
This is the first research effort to demonstrate the potential effects of pot on UGT enzymes, the researchers say. The study also sheds more light on marijuana’s effect on CYP enzymes.
It’s been known for some time that pot could interact with other drugs, Paul Armentano, deputy director of NORML, a group that advocates for the reform of marijuana laws shares.
The U.S. Food and Drug Administration’s labeling of a form of synthetic THC called dronabinol, which has been available as a prescription drug for more than 30 years, indicates that it might influence CYP levels, Armentano notes. And the agency’s warning for Epidiolex, a plant-based prescription CBD drug, also addresses how the substance could affect the liver, he adds.
But Armentano questioned how powerful these interactions could be, given how long marijuana has been used both recreationally and medicinally.
“Adults — and patients in particular — have been consuming cannabinoids medicinally for centuries, and this practice has become quite commonplace over the past few decades,” Armentano says. “Many of these patients are older and many of them may also be prescribed other medications. Were cannabinoids to be significantly contraindicated among this population, one would presume that there would be ample empirical evidence already available substantiating this concern.”
Pot’s effect on metabolism wouldn’t likely affect someone who takes a recreational toke or three on the weekend, according to Lazarus.
“Even though it probably inhibits these enzymes, it doesn’t inhibit them enough to interfere with your everyday metabolism,” Lazarus acknowledges.
The problem comes when you mix regular pot use with other drugs, or if you’re taking a marijuana-derived product alongside your prescription.