Health Advice



Are your medications' benefits going up in smoke?

By Michael Roizen, M.D. on

You may think the cannabis craze is a recent phenomenon now that recreational marijuana has been legalized in 18 states plus Washington, D.C., and Guam. But Gertrude Stein's partner published a recipe for "Haschich Fudge" in her self-titled "The Alice B. Toklas Cook Book" in 1954.

In the intervening 68 years, folks haven't gotten smarter about watching out for possible hazards that go along with smoking or munching marijuana and taking in its active components, THC, CBD and CBN.

Those cannabinoids may benefit some folks, but they also can interfere with the effects of (other) medication you're taking. Two lab studies published in the journal Drug Metabolism and Disposition reveal that they disrupt the working of two families of enzymes that help your body process a wide range of drugs. In fact, together, these two enzyme families help metabolize and eliminate more than 70% of the most commonly used medications from the body.

When these enzymes cannot do their job, a medication's benefits might decrease or its negative side effects might increase -- causing overdose, toxicity or other harmful reactions. Especially risky: the interaction with cancer-fighting drugs and the impact on reduced kidney function. Important fact: The enzyme-disrupting effects last for 14 days after using cannabis.

That's why it's important to tell your doctors if you're smoking marijuana (don't; it's bad for your lungs) or using edibles or topical CBD. If you are and a medication isn't working or you're having a negative reaction to it, cannabis might be the reason for the problem.



Health pioneer Michael Roizen, M.D., is chief wellness officer emeritus at the Cleveland Clinic and author of four No. 1 New York Times bestsellers. His next book is "The Great Age Reboot: Cracking the Longevity Code for a Younger Tomorrow." Do you have a topic Dr. Mike should cover in a future column? If so, please email

(c)2022 Michael Roizen, M.D. and Mehmet Oz, M.D.

Distributed by King Features Syndicate, Inc.

(c) 2022 Michael Roizen, M.D. Distributed by King Features Syndicate, Inc.



Baby Blues Joey Weatherford Ed Wexler 1 and Done Ginger Meggs Brian Duffy