Medically Reviewed by
Jason Crawford

Article Last Updated on January 2, 2023

Drug interactions are a common concern whenever you’re taking any medications because of the unique chemistry they all contain. Cannabis has many times been proven to have many medical benefits, from chronic pain relief and anti-inflammatory action to improving sleep quality. Therefore, it’s already being used as medical marijuana to treat the symptoms of various conditions.

However, it’s also known that just like many other substances, cannabis interacts with certain classes of medications. But are antibiotics among them?

Antibiotics are the primary drugs given for bacterial infections and they’re very commonly used, so it’s natural to wonder if they can cause any adverse reactions with cannabis. Therefore, in this article, we’ll talk about drug interactions and whether you can smoke marijuana while on antibiotics.

How Harmful Are Drug Interactions and What Side Effects Can They Cause?

Drug interactions happen when you take one or more medications and they react with each other. The same can also happen with any foods or beverages that contain certain ingredients that don’t agree with the ingredients present in certain medications.

Drug interactions can make the drug less effective or heighten its effects, putting you at risk of experiencing negative reactions and toxicity, or it can worsen a medical condition you already have. Most drug interactions don’t cause any severe adverse effects, however, since side effects are still possible, you need to be cautious and informed about the possible outcomes. 

These are the categories that drug interactions fall under:

  • Drug-drug interactions happen when two or more meds react with each other. One can either decrease the effectiveness of the other or increase the possible minor or major side effects. There is a higher risk when more medications are involved;
  • Drug-food/beverage interactions occur when certain medications react with a certain food or beverage. One example is alcohol as it can heighten the effects of certain drugs, and another example is grapefruit juice because it inhibits the absorption of some over-the-counter and prescription medications;
  • Drug-medical condition interactions can happen when a certain drug worsens your medical condition. An example of this is over-the-counter oral decongestants that can increase your blood pressure if you suffer from hyperthermia.

What Type of Drugs Are Antibiotics?

Antibiotics are perhaps the most common medication prescribed for bacterial infections. They slow down or inhibit the growth of bacteria which is why they’re widely used to treat or prevent these infections. For all the benefits they have, they sometimes can disrupt the natural bacterial flora in your digestive tract, resulting in an upset stomach and diarrhea. 

There are different types of antibiotics that can destroy different types of bacteria. However, overuse of antibiotics can have the opposite effect and create more resistant bacteria.

You probably already know that when you’re prescribed to take any type of antibiotic, you’re advised to avoid drinking alcohol as it can not only make the antibiotics less effective but also cause side effects such as drowsiness.

But, is it the same with other intoxicating substances, such as weed?

Can I Smoke Weed While on Antibiotics?

Even though cannabis is a relatively safe substance, it can have drug interactions with certain medications. 

Cannabis inhibits the so-called cytochrome P450 enzymes which are a superfamily of liver enzymes responsible for the metabolism of cannabis and some classes of medications, including some antibiotics. This means that cannabis interacts with the enzymes and won’t allow for proper absorption of these meds. The result is either heightened or weakened effects of the medications.

However, regarding smoking weed and antibiotics, there seem to be very mild drug interactions. In fact, antibiotics aren’t even included on the list of drugs with possible contraindications with cannabis. That doesn’t mean that there is no risk at all as certain antibiotics, such as macrolide antibiotics like troleandomycin, erythromycin, and miocamycin can cause some mild side effects.

That being said, there is still a lot to research regarding cannabis and its interactions with different medications. However, regarding antibiotics, it doesn’t appear to cause any serious side effects. Of course, if you’re on antibiotics and are thinking of smoking weed, you should still get proper medical advice as everyone’s body is different.

Cannabis Use and Other Drug Interactions

Thankfully, there is some reliable research regarding cannabis use and different meds, but this is just the tip of the iceberg. With the legalization of recreational and/or medical marijuana when nearly anyone can buy weed from a dispensary, being informed about drug interactions with cannabis is important.

The major cannabinoids THC and CBD may have many benefits, but they could still cause some adverse side effects when mixed with anticoagulants, antihistamines, opioids, beta-blockers, and others. You can find the full list of major and moderate drug interactions with cannabis here.

Cannabis May Have Antibacterial Properties

There is some preliminary research that suggests that marijuana can have antibacterial properties. A 2008 study looked at the antibacterial properties of not only THC (tetrahydrocannabinol), the psychoactive cannabinoid, and CBD (cannabidiol), the therapeutic cannabinoid, but also CBG (cannabigerol), CBN (cannabinol), and CBC (cannabichromene). 

They tested the effectiveness of the cannabinoids against different varieties of MRSA bacterial strains and found that all were effective. The method of action seems to be due to cannabis’ interaction with the cannabinoid receptors in the body which impacts the immune system.

Another study from 2020 discovered that CBD can help enhance the antibiotic action of Bacitracin against Staphylococcus aureus bacteria, which is notorious for its antibiotic resistance. The researchers discovered that CBD was able to stop its growth. 

Despite these discoveries, there is a lot more left undiscovered. Even though the cannabis industry is expanding, it’s still too early to think about whether marijuana use can replace antibiotics.

Bottom Line – No Known Contraindications, but Remain Cautious

Drug interactions happen when two or more drugs react with each other, causing increased side effects or influencing the absorption of the drug in the body. Even though cannabis can react with several different classes of medications by interfering with their metabolism in the liver, so far there aren’t any known contraindications with antibiotics, except for macrolide antibiotics. However, whether you’re using medical cannabis or smoking marijuana for pleasure, it’s always good to consult with a doctor if you’re taking antibiotics.

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.