is smoking weed before surgery bad

How Marijuana Can Affect Your Surgery

Scott Sundick, MD, is a board-certified vascular and endovascular surgeon. He currently practices in Westfield, New Jersey.

If you smoke marijuana and are planning to have surgery you may be wondering if you need to stop smoking before your procedure. Like smoking cigarettes, the short answer is this: Yes, quitting today may improve your surgical outcome, how quickly you get out of the hospital, and how quickly you heal after surgery.

Marijuana Before Surgery

Like nicotine, marijuana can complicate surgery and should be avoided in the weeks and even months prior to your procedure. Much like smoking cigarettes, abstaining from marijuana in the weeks before surgery can decrease the likelihood of complications during and after surgery.

Unfortunately, research on the topic of marijuana use and the effects during surgery is limited. It should become more plentiful in the future as medicinal marijuana has been legalized in multiple states (and recreational use in a growing number), making it easier to gather scientific data on the topic.

We do know that marijuana, while effective for decreasing nausea and some other health-related benefits, has the potential to interact with anesthesia.  

Risks of Smoking Marijuana

Contrary to popular wisdom, marijuana smoking is not a healthier option than cigarettes. It can lead to lung cancer and other respiratory problems.  

The process of inhaling large amounts of marijuana, then holding it in the lungs for extended periods of time to increase the amount absorbed, leads to increased exposure to cancer-causing chemicals.

The chronic coughing, wheezing and difficulty breathing that long-term cigarette smokers experience also occur in marijuana users.  

Types of Marijuana

When talking about surgery anesthesia and marijuana, all types of marijuana should be avoided. That means smoking marijuana, edibles, and synthetic marijuana.

Synthetic marijuana, in particular, is poorly understood, unregulated, and highly variable in content. For this reason, it is impossible to predict the reaction that might occur with exposure to anesthesia. Synthetic marijuana should not be used in the days, or even weeks, prior to surgery.

Marijuana and Anesthesia

Smoking marijuana regularly leads to the same risks of complications faced by patients who smoke cigarettes. This means that marijuana smokers are more likely than non-smokers to be on the ventilator longer, have a higher risk of developing pneumonia after surgery, and greater scarring of incisions.

The use of marijuana, especially immediately prior to surgery, can change the doses needed for sedation.   One commonly used medication, propofol, requires substantially higher doses for the patient who routinely uses marijuana.

One study looked at the doses of propofol required to intubate patients who routinely smoked marijuana with non-marijuana using patients.   The individuals who used marijuana required a dramatic increase in sedation.

One patient who smoked marijuana 4 hours prior to surgery was the topic of a case study, after experiencing an airway obstruction during the procedure.   This is a very serious complication that can lead to death, and is believed to have been caused by airway hyperreactivity, a condition known in cigarette smokers but previously unidentified in marijuana users.

It is also believed that regular users of marijuana—whether it is smoked or eaten—are more likely to experience agitation.

Marijuana Effects During Surgery

The use of marijuana the day before surgery, and especially in the hours prior to the procedure, can cause more dramatic effects.   While some people are tempted to use marijuana prior to surgery in an effort to relax or be less stressed before the procedure, this is a very bad idea and can cause problems.

Marijuana causes the blood vessels of the body to relax, a process called vasodilation. This process can cause the blood pressure to fall and the heart rate to increase. These, in turn, can complicate matters if the patient’s blood pressure is falling due to issues with the surgery, and can change the way the body responds to anesthesia.

Tell the Truth About Marijuana Use

It is very important that you are candid with the anesthesia provider about your personal use of marijuana. This means giving an accurate report of how much and how often you use marijuana, whether you eat it or smoke it, and when you last did so.

It is unlikely that your use will delay your surgery, but it is important that the anesthesia provider understands the potential for your body to need more anesthetic than is typical.

The anesthesia provider also needs to be prepared for any airway issues that may arise, which are more common in smokers of all types compared to non-smokers.

After Surgery

Regular marijuana use, like cigarette and cigar use, can increase the length of time it takes to be removed from the ventilator after surgery.   The risk of being on the ventilator long term is decreased by quitting smoking before surgery, and that risk is decreased further with every day that passes between the last day of smoking and the day of surgery.

A Word From Verywell

It may seem like a drag—pardon the pun—to stop smoking marijuana before surgery and to not smoke during your recovery from surgery, but you will heal faster, return to your normal activities more quickly, have less scarring and fewer complications if you refrain.

It is true that most people would have quit smoking long ago if it were easy, but surgery offers a real incentive to back away from the marijuana (and nicotine) in order to have the best possible outcome after surgery.

Every day you go without smoking prior to surgery will decrease your chances of being on the ventilator longer than the average patient, and will decrease the length of your stay in the hospital.

Smoking pot before surgery can cause problems during and after your procedure, find out why you should avoid marijuana before surgery.

Is Cannabis Safe To Use Before And After Surgery?

Given the anxiety-inducing nature of surgery, cannabis users may be tempted to smoke up before going under the knife. But all things considered, is this a good idea? Here is a rundown on consuming weed pre and post-surgery.

No matter why you’re going under the knife, recovering from surgery can be quite painful. Post-operation, doctors will usually prescribe painkillers. However, most drugs like opioids can be highly addictive and are equipped with tons of side effects. Opioid addiction is no longer a phantom—many in the US and around the world are falling victim to this full-blown epidemic.

The most unfortunate thing to learn is that many started their addiction shortly after being prescribed painkillers like oxycodone or hydrocodone post-surgery. Though many surgeons wish to prescribe their patients with fewer painkillers, some patients still face life-threatening consequences. This is enough reason for many to seek out other forms of pain relief. Research [1] has shown that cannabinoids found in marijuana help soothe pain for a multitude of conditions, but the top question is, are there any contraindications to consuming marijuana before or after surgery? The answer is not a simple yes or no. It relies on a few variables such as time of consumption, medical history, and the nature of the strain.


While rolling up a fat joint sounds pretty enticing before surgery, mixing marijuana with anaesthesia can produce some pretty negative effects on the body.

Smoking marijuana before surgery can increase mucus production in your respiratory tract, which can be an issue while under the knife. However, smoking more than a few hours before your surgery time will likely offer you a great enough window for the effects to wear off, thus reducing sputum in the fluids of your sinuses and lungs. Nonetheless, if you’re a frequent user, it’s crucial for the sake of your health that you keep it real and talk to your doctors about your use before any surgical procedure.


While research has been conducted on the negative effects of prescribed painkillers after surgery, there is still much to research on the effects of weed after a surgical procedure. The healing process gets interrupted by excessive coughing, so although you might be a master bong ripper, vaping or edibles will be your best bet for an easy transition.


Dental work often leaves patients with sore, inflamed gums, so small quantities of cannabis afterward could provide some health benefits [2] . As we know, cannabis has a ton of anti-inflammatory and antibacterial properties, so if you experience serious dental surgery pain, cannabis could provide significant relief without the need for high-strength pharmaceutical painkillers.

However, there is one downside. You may suffer from some serious cottonmouth from consuming cannabis after dental surgery. If you’re worried, there are a number of safe ways to get high. Try using means like ingesting edibles, tinctures, or oils. These will provide much more relief and will delay the onset and severity of dry mouth.


The medical industry likely has a long way to go before prescribing cannabis post-surgery, not just because it isn’t federally legal, but because the pharmaceutical industry’s dominance is so entrenched in modern Western society. As such, discuss the possibility of cannabis consumption with your doctor; they will warn you if there are likely to be major contraindications.

While cannabis is beneficial in helping with numerous conditions, its use after surgery is still in question. Find out the pros and cons of post-surgical weed.