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Medical Marijuana Users May Require More Anesthesia During Surgery

Millions of people use marijuana. Many rely on cannabis for medical reasons such as nerve pain. People taking marijuana may need more anesthesia than usual.
Pot drugs cannabis medical marijuana

Millions of people are now using cannabis regularly. Some smoke marijuana. Others eat marijuana gummies, brownies, chocolate bars, truffles and chocolate chip cookies. Then there is medical marijuana. Patients with nerve pain, cancer, Crohn’s disease, anorexia, epilepsy, multiple sclerosis, muscle spasms and nausea are also using cannabis. A new study suggests that all these people should be aware that they may need higher doses of certain anesthetics during surgical procedures. Otherwise, they may not achieve adequate levels of sedation or anesthesia.

More Anesthesia for Marijuana Users:

When it comes to procedures that require general anesthesia, cannabis users may have to be more candid about their use of marijuana. That’s because a new study suggests that regular use of cannabis can dramatically impact the dose of anesthetic needed (Journal of the American Osteopathic Association, online April 15, 2019).

In this study, 250 Colorado residents underwent minimally invasive procedures such as colonoscopies. Marijuana is legal in Colorado and 10 percent of the patients said they used cannabis regularly.

These people required more than twice as much propofol for anesthesia compared to nonusers. In addition, they needed 20% more midazolam for sedation. If a powerful opioid pain reliever like fentanyl was required, the dose of that drug also needed to be a bit higher.

Why This is Important:

Inadequate anesthesia is not a good thing. If someone wakes up in the middle of major surgery, it can be a devastating experience. That’s especially true if the surgeons have administered a powerful muscle relaxant. The patient won’t be able to let the surgeons know the anesthetic isn’t doing its job.

Post-surgical pain relief might also be impacted by marijuana use. If someone gets a standard dose of fentanyl and it doesn’t work as anticipated, it could be hard to convince a physician that a higher dose of the opioid is necessary.

That might also be true for cancer patients. Many people getting chemotherapy experience hard-to-treat nausea and vomiting. Sometimes they turn to medical marijuana to overcome this devastating side effect. Cancer patients may also require opioid pain relief. If marijuana partially attenuates the pain relieving impact of fentanyl, health professionals need to know that doses might require cautious upward adjustment.

Communicating About Marijuana and More Anesthesia:

Anesthesiologists don’t always ask ahead of time if their patients are marijuana users. Patients may not volunteer such information without prompting unless they understand how cannabis use could impact their reactions to anesthesia. The new research means that patients must be candid about their use of marijuana and anesthesiologists will need to ask and possibly adjust the dose of the drugs they use during surgical procedures.

Have You Ever Used Marijuana?

If you have used marijuana recreationally or for medical reasons, please share your experience below in the comment section. Did you ever need anesthesia while using cannabis? Was there a problem? 

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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I don’t think all politicians are dishonest and just say what they think people want to hear, whether it’s on the subject of marijuana, the border issue, equal rights, climate change, or any other subject. Yes, many voters want legalization of at least CBD for pain relief, whether pot with THC comes along later or not for recreational users. Politicians are supposed to vote as a representative for what the majority of his/her constituents want.

In Texas, the majority of voters are in favor of CBD oil and hemp being legal since no one has shown up at any recent public committee session to protest at all. But many who were in favor did speak their minds. It looks like CBD oil and growing hemp will pass soon in Texas.

I am a person in pain who wants at least the freedom to choose trying CBD to see if will help me take less opioids and other pain RX’s. I was run down by a driver who didn’t stop and hit me again, trying to flee the scene. I’m in severe pain 24/7. Refusing to listen to scientific facts about a possible solution and clinging to an emotional reaction to any subject is a disservice to all.

I recently had an endoscopy with anesthesia while using cannabis on a regular basis. I had no problems, but in the future will disclose to the anesthesiologist. Most probably don’t know this effect which is why they don’t screen you with the question.

Doctors, the FDA, researchers and even chemists that test for cannabis compounds all say the same thing: so much research is needed. I believe a major stumbling block to research is the high variability in the potency (both CBD and THC) in the various products with very differing reactions from people. We are in the “wild west days” of both (legal) medical and recreational marijuana. All cannabis should be legalized and regulated on a national level like alcohol and cigarettes. However, the black market “dark ages” for pot will never go away as long as their pricing remains significantly below the legal recreational brand.

I have never used Marijuana, I am waiting for Cannabis liquid tincture for pain relief, I live in North Carolina, they will vote in Raleigh in May 2019 , Hope we get it.

I support legalizing marijuana because we desperately need the research to know more about this drug — both benefits and dangers.

As a cancer patient, I use medical marijuana as a sleep aid. I only take it at nighttime, but I take a significant dose. I always disclose my cannabis use to my medical providers. I had outpatient surgery a few months ago without any complications.

There is a difference between marijuana and CBD products. While some CBD products contain 3% or less of THC, most are completely free of THC, which is the psychotrophic element in marijuana. Research needs to be done to carefully distinguish between these two products. Your article needs to be specific as to which products you are discussing, as there is are BIG differences among smoking recreational marijuana, using medical marijuana, and using CBD products.

As a former ER nurse I beg you to please be candid about all medications and drugs that you are using. This includes nutritional supplements. Most nurses and doctors have heard worse and if they find out later that you have intentionally withheld information they will have a hard time believing what you say going forward.

Politicians support legalizing pot because it buys votes.

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