The cannabinoids found in marijuana and their metabolites could negatively interfere with a range of prescription drugs. According to researchers at Washington State University, using marijuana in combination with prescription drugs can either decrease the positive effects of the drugs or increase their negative side effects. In some cases, the mixture of the two can also cause toxicity and accidental overdose.
“Physicians should be aware of the possibility of toxicity or a lack of response when patients use cannabinoids,” said Philip Lazarus, senior author of the papers and professor of pharmaceutical science at Washington State University. “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. “
Lazarus and his colleagues published a pair of studies that investigated the interactions between cannabis and two families of enzymes which together are responsible for the metabolism and elimination of over 70% of the most commonly used pharmaceutical drugs. . One study focused on cytochromes P450 (CYP), while the other looked at UDP-glucuronosyltransferases (UGT).
The full analysis not only examined the roles played by the most abundant and important cannabinoids – tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) – but also their metabolites, the intermediate products of reactions. metabolic processes catalyzed by various enzymes that occur naturally in cells.
Cannabinoids like THC or CBD stay in your body for just 30 minutes before being broken down into smaller molecules, each with different effects. These metabolites persist in the body for much longer, up to 14 days in some cases. They also accumulate over time with continued use, so their concentration may be higher than the original cannabinoids. But despite their importance, the impact of these metabolites during interactions with other drugs has been overlooked by previous studies.
The researchers first worked with individual human kidney cells that allowed them to zoom in on just one enzyme at a time, then validated their results in human liver and kidney samples where many of these enzymes were present.
The results showed that cannabinoids and the major metabolites of THC inhibited several CYP enzymes, especially those found in the liver. All three cannabinoids, especially CBD, inhibited two of the major UGT enzymes found in the liver. CBD has blocked three enzymes that make up 95% of the kidney metabolism of UGT, which plays a major role in removing toxins and certain drugs from your system.
“If you have kidney disease or if you take one or more drugs that are mainly metabolized by the kidneys and you also smoke marijuana, you may be inhibiting normal kidney function and this may have long term effects on your kidneys. you, ”said Lazare.
Many patients take prescription drugs for a variety of chronic conditions, from diabetes to cancer. These conditions are painful to experience, which is why some patients self-medicate with cannabis or cannabis-derived products like CBD. But using these anti-inflammatory products can end up doing more harm than good when combined with certain medications.
“Taking CBD or marijuana might ease your pain, but could make the other drug you’re taking more toxic, and this increase in toxicity may mean you can’t keep taking this drug,” the former said. author Shamema Nasrin, a graduate student. at the WSU College of Pharmacy and Pharmaceutical Sciences. “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.”
Both studies were published in the journal Drug metabolism.