Some things don’t mix. With this in mind, it is always important to be aware and cautious of what you’re taking when on any sort of medication, since certain medicines will have a negative or more enhanced reaction when taken with another substance. Case in point: When you’re fighting off a bacterial infection, doctors generally prescribe antibiotics, which come along with some strict rules. But almost never addressed is an important question: can you smoke weed while taking those antibiotics?
High Times decided to ask Terry Roycroft, the president of Canada’s Medicinal Cannabis Resource Centre Inc. (MCRCI), which works with doctors who have a special understanding of the medical applications of cannabis. Roycroft has studied marijuana and its effects for over a decade and is highly passionate about advancing public knowledge of the plant. Thankfully, according to him, taking antibiotics and smoking marijuana may not be as harmful to an individual as one would initially think.
How Harmful Are Interactions?
“There’s a number of drug interactions for numerous everyday things. For example, even with caffeine, there are 82 drug interactions out there and some of them are moderately severe to severe,” Roycroft explains.
According to the UK’s National Health Service, it’s “sensible” to stay away from drinking when taking antibiotics, although only two medications call for completely avoiding alcohol altogether: metronidazole and tinidazole. Even something as harmless as grapefruit can have a negative interaction with antibiotics. This piece of fruit can interfere with the metabolism of a number of medications, including some antibiotics used to treat certain respiratory, stomach and other infections. In fact, Roycroft says that they began using grapefruit as a guide for cannabis.
“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,” Roycroft says.
Any interactions that have been identified are very mild — and, in fact, doctors are currently testing to see if some antibiotics work more favorably mixed with marijuana.
“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.”
Although there may be very mild interactions, effects may still be felt by those who mix the two. According to Jessie Gill, a medical nurse who specializes in medical marijuana, using some macrolide antibiotics, such as troleandomycin, could potentially interact with marijuana.
“Marijuana inhibits a specific enzyme in the liver, cytochrome p450. This enzyme is used by many medications – including some antibiotics,” Gill wrote on Quora.
“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.”
What About Taking CBD?
Interestingly, studies have shown that CBD may, in fact, actually have antibiotic properties. Newsweek reports that Australian scientists have discovered that cannabidiol killed numerous strains of bacteria, including some that have been notoriously resistant to traditional antibiotics. But so far, it still seems like CBD has a long way to go, in terms of replacing antibiotics altogether.
“We still don’t know how it works, and it may have a unique mechanism of action given it works against bacteria that have become resistant to other antibiotics, but we still don’t know how,” Mark Blaskovich, senior research chemist at the Centre for Superbug Solutions, told Newsweek.
“So far, we have only shown it works topically, on the skin surface. To be really useful, it would be good if we could show that it treated systemic infections e.g. pneumonia, or complicated tissue infections, where you have to give it orally or by intravenous dosing. A very preliminary study didn’t show that it works in these more difficult models.”
So, Should You Consume Cannabis on Antibiotics?
All in all, Roycroft says there’s really no issue with mixing cannabis and antibiotics. You may just experience increased side effects of the medication.
“At the Medicinal Cannabis Resource Centre Inc., we have patients on antibiotics and we would not tell them to stop their cannabis use,” Roycroft says.
As for other doctors, they will sometimes use grapefruit as a guide for cannabis. If there is a contraindication with grapefruit, then you may not want to mix cannabis with the medication.
If it is still an issue you’re concerned about, ask your doctor what they recommend — after all, there’s nothing wrong with receiving additional medical advice from a professional.