Can smoking marijuana affect general anesthesia?

Ask The Doctor > Marijuana > Can smoking marijuana affect general anesthesia?

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Patient: I am scheduled to go under general anesthesia for dental surgery (wisdom teeth extraction, implant, and possible bone graph from jaw depending on the strength of the implant site). I smoke marijuana on a regular basis and I am concerned about how this may affect the anesthesia. I know this is something I should discuss with my anesthesiologist however my Mom is present for many of the appointments even though I am legally an adult and I do not want her to know. Am I at risk? Will the THC lingering in my body affect the anesthesia? How many days before the surgery should I stop smoking?

Doctor: There are two factors to consider here. The first is smoking. Smoking affects the airways and makes them more reactive t hat the non-smoker. This means that your airways may respond negatively to anesthesia making it a little difficult to deliver oxygen while you sleep. The anesthesiologists do have ways of counteracting that effect.The second factor to consider is the marijuana itself. The drug tends to interact with a number of medications generally decreasing their effects.I would suggest you stop smoking two weeks before the procedure and be sure to inform your doctor that you use marijuana as well as the fact that you are on Prozac. You can ask to speak with your doctor without your mother present. Any information you share with the doctor will not be revealed to your mother without your consent.

Comments / Follow Ups

Doctor: Thank you for the question. I know Awake is a scary movie. For non-movie buffs, Awake is a movie where a person is under general anesthesia but can feel everything that is going on. The surgery being performed is hurting the person but the person is paralysed and not able to move or tell anyone about this.

This is a truly very scary scenario and I would like to tell you this is all fiction but that is not the case at all. The condition is is known as anesthesia awareness and occurs in 2 to 4 of 1000 surgeries.

Usually, it occurs when the person is not given the medication properly and is unable to move but can feel some sensation.

Usually, the person is tied with a tourniquet to allow his forearm to not be paralyzed by anesthetic so the person can respond by moving it and the anesthetist knows the person is awake.

Getting back to the original question. Yes, a lot of drugs are made of similar drugs to those in weed. And they will cause the anesthesia effect to be less. And people who take drugs are more likely to get a anesthetic complication.

So please do not take marijuana and if you do take it please tell your Doctor. Marijuana can cause dangerous problems before a general anesthesia. A miscalculated dose will be fatal.

Dr. Jimmy Obaji M.D.

Dr. Jimmy Obaji completed his residency in Family Medicine at the University of Manitoba. He currently operates a walk-in-clinic in downtown Toronto.

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