Cannabis Science

Can you smoke weed while on antibiotics?

Can you smoke weed while on antibiotics?

As you’ve probably heard or experienced, antibiotics don’t mix well with certain drugs. For example, doctors will tell you to avoid alcohol when undergoing treatment with antibiotics. Antibiotics may even be affected by certain foods. For example, you may have been told to avoid dairy products with some and grapefruit with others. If you’re someone who enjoys smoking weed but had an infection you need antibiotics for you to be wondering if you could use both simultaneously. Featured Image: Unsplash

Can you smoke weed while on antibiotics?

There is not a whole lot of information on marijuana’s interaction with antibiotics. However, according to the Terry Roycroft, the president of Canada’s Medicinal Cannabis Resource Centre Inc. (MCRCI), who was quoted in High Times, the interaction between the two drugs may not be as dangerous as people would imagine. 

Roycraft said, “The reality is that there [are] very little interactions with cannabis. In fact, the antibiotics are not on the contraindicator list [the list of symptoms or conditions that makes a procedure inadvisable] with cannabis,”

The article went on to mention that scientists are looking at whether or not marijuana may even help to improve the effectiveness of some antibiotics. 

Roycraft, who works with doctors who are educated in medical cannabis says they cut antibiotic doses in half if they have a patient who uses cannabis. He said, “For instance, when we’re treating someone that’s on pain medication and we introduce cannabis, we will cut their [antibiotic] dose in half immediately and they get the same benefits as they would, and the same reactions as if they were taking the full amount.”

He concluded by saying that you may have an increased side effect of some of the antibiotics but it’s relatively safe to use marijuana and antibiotics. Roycraft mentioned that there people at the clinic who are antibiotics and they are not advised to stop using cannabis. However, he did say that some doctors use the grapefruit as an indicator as to whether or not it’s safe to use weed and antibiotics simultaneously. All that means is if grapefruit would cause adverse side effects when you take the antibiotic then they wouldn’t recommend you use weed while on it. 

What Others Say About The Interaction of Weed and Antiobotics 

Hightimes also referenced a nurse, Jessie Gill, who specializes in medical marijuana and posted on Quora about weed and antibiotics. It seems her response has been removed but according to High Times, weed may interfere with some antibiotics and cause negative effects. 

According to Gill, “Marijuana inhibits a specific enzyme in the liver, cytochrome p450. This enzyme is used by many medications – including some antibiotics. What this means is that the effect of the medications will be increased. That also means you’d be at a higher risk of experiencing side effects and adverse reactions from the antibiotics.”

Does weed interfere with other medication?

According to, 377 drugs are known to interact with weed. Of the 377, 24 are major drug interactions and 353 are moderate drug interactions. 

Major Drug Interactions with Weed

Some drugs, when used alongside weed can produce harmful effects. For example, using morphine with weed can cause respiratory distress, coma, and death. The reason why this combination may be lethal is that they both cause central nervous depression. The article said, “Using narcotic pain or cough medications together with other medications that also cause central nervous system depression can lead to serious side effects”. As you know, marijuana can produce depressant effects. 

Another drug that has major interactions with weed is Tramadol. Tramadol is another pain reliever for moderate to severe pain. It’s dangerous for the same reasons morphine and marijuana are a bad combo. 

Moderate Drug Interactions with Weed

A number of medications or drugs interact to have a moderate reaction with weed. One such drug is alcohol. According to, alcohol and weed together may cause dizziness, drowsiness, confusion, and difficulty concentrating, impairment in thinking, judgment, and motor coordination.

Other drugs that have a moderate interacion with weed are: 

  • Amitriptyline
  • Ativan (lorazepam)
  • Benadryl (diphenhydramine)
  • Cymbalta (duloxetine)
  • Flexeril (cyclobenzaprine)
  • Klonopin (clonazepam)
  • Lexapro (escitalopram)
  • Lyrica (pregabalin)
  • Seroquel (quetiapine)
  • Xanax (alprazolam)
  • Zoloft (sertraline)
  • Zyrtec (cetirizine)

Drugs with No Interacton Found With Weed

According to, just because there was no interaction found. The website urges readers to consult their healthcare providers about mixing the drug with weed. Here is the list provided:

  • Adderall (amphetamine / dextroamphetamine)
  • ibuprofen
  • Paracetamol (acetaminophen)
  • Tylenol (acetaminophen)
  • Vitamin B12 (cyanocobalamin)
  • Vitamin C (ascorbic acid)
  • Vitamin D3 (cholecalciferol)
  • Wellbutrin XL (bupropion)
  • Zofran (ondansetron)


While there isn’t much information on how weed affects antibiotics, it’s probably best to err on the side of caution. All antibiotics are not the same and while some drugs or food are fine with some, that may not be the case with others. Using antibiotics with weed seems to be relatively safe and you’ll probably be okay. However, the best thing to do is to consult your health care provider and get their opinion before you mix the two drugs. Querying the interaction between two drugs is good practice since as you can see, some combinations could be deadly.


About Trevann

Trevann is Stoner Rotation’s Jamaica-based lead writer for the Science section of our cannabis blog. She graduated with honors receiving her Bachelor of Science degree in Molecular Biology from the University of West Indies, Mona. For the last three years, she has covered some of the biggest questions around cannabis and health underpinned with research from supporting studies, medical journals and scholarly articles. Got something on your mind? You can reach her at [email protected].