New research from scientists at Washington State University indicates that using medical cannabis with various prescription drugs can be accompanied by significant risk.
Researchers have found that several major cannabinoids and their metabolites can interfere with two families of enzymes – cytochromes P450 (CYP) and UDP-glucuronosyltransferases (UGT) – which play a role in the metabolism of a wide range of prescribed drugs. for various ailments. This could lead to an amplification of the therapeutic effects of these drugs or an increase in their negative effects. Increasing the positive effects is not a good thing as there can be a very big difference between therapeutic and toxic doses.
Lead author Philip Lazarus said physicians should be aware of the possibility of toxicity or lack of response in patients using cannabinoids.
“It’s one thing if you’re young and healthy and smoke cannabis every now and then, but for older people who are on medication, taking CBD or medicinal marijuana can have a negative impact on their health. processing. “
The team’s research found that the major metabolites of THC strongly inhibited several key CYP enzymes in the liver. Additionally, three cannabinoids – but in particular CBD – inhibited two of the major UGT enzymes found in the liver. Additionally, CBD has also been found to block three enzymes that make up pretty much all of UGT metabolism in the kidneys. This is of particular concern because the metabolism of UGT purges toxins and certain drugs from the body.
First author Shamema Nasrin said that kidney disease or cancer patients who smoke marijuana or use CBD and take prescription drugs may have inhibited kidney function with potential long-term effects.
“So there could be serious ramifications for anticancer drugs, and this is just one example of the many drugs that could potentially be affected by the cannabinoid-enzyme interactions that we are seeing.”
The study was published in the journal Drug Metabolism & Disposition and can be viewed in full here.
The warnings from the Washington State University team are not the first of this nature. Last year, researchers at Penn State College of Medicine said products containing cannabinoids could impact the effects of some conventional prescription drugs, including commonly used blood thinners, antibiotics, anticonvulsants and pain relievers. .