Study: Using cannabis with other medications carries risk

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Cannabis use with other drugs may come with significant risks, a new study from Washington State University Suggests.

Researchers with the university looked at cannabinoids and their metabolites and found that they interfere with enzymes that help metabolize drugs that are prescribed for a range of conditions, according to a release from earlier this week.

“Physicians need to be aware of the possibility of toxicity or lack of response when patients are using cannabinoids,” Philip Lazarus, senior author on the papers and Boeing distinguished professor of pharmaceutical sciences, said in the release. “It’s one thing if you’re young and healthy and smoke cannabis once in a while, but for older people who are using medications, taking CBD or medicinal marijuana may negatively impact their treatment.”

According to the study, the desired effects of the prescribed drugs could decrease or negative side effects could increase with the way that cannabinoids interfere with the enzymes.

The research findings were published as a pair of studies in the journal Drug Metabolism and Disposition. One study focused on one of the families of enzymes called cytochrome P450s and the other study focused on the other family called UDP-glucuronosyltransferases.

The two enzyme families combined metabolize more than 70 percent of commonly used drugs.

“Cannabinoids stay in your body only for about 30 minutes before they are rapidly broken down,” Shamema Nasrin, a graduate student in the College of Pharmacy and Pharmaceutical Sciences at WSU and first author on the research, said in the release. “The metabolites that result from that process stay in your body for much longer—up to 14 days—and at higher concentrations than cannabinoids and have been overlooked in previous studies, which is why we thought we should focus on those as well.”

The researchers used manipulated kidney cells where they could look at a single enzyme at a time. Through this process, they found that cannabinoids and major THC metabolites could strongly inhibit the first family of cytochrome P450 enzymes and that the cannabinoids, especially CBD, inhibited the second family of enzymes, the UDP-glucuronosyltransferases.

These effects on the enzymes could ultimately inhibit kidney function, according to the authors. This could especially be prevalent in patients with kidney disease or kidney cancer who use CBD or other cannabis products for pain treatment or to mitigate side effects.

The authors still say more research needs to be done, but one takeaway is that consumers should be careful when using cannabis products with prescription drugs and medications.