Can You Use Cannabis While Taking Binimetinib (Mektovi)?

Hello! I appreciate you checking on this before combining the two; it's exactly the kind of question worth asking during cancer treatment.

Cannabis is not known to have a major, documented interaction with binimetinib (brand name Mektovi), and based on how binimetinib is processed in the body, a significant interaction isn't expected.

That said, the combination hasn't been formally studied as far as I am aware, and because binimetinib is part of a serious cancer regimen, this is something your oncology team should know about and sign off on.

How Our Body Processes Binimetinib Why That Matters

Binimetinib is a targeted therapy known as a MEK inhibitor, most often prescribed together with encorafenib (Braftovi) for certain melanomas with BRAF mutations.

One reassuring point is that binimetinib is broken down mainly through a process called glucuronidation (primarily by an enzyme called UGT1A1) rather than relying heavily on the CYP450 liver enzymes that are behind most cannabis-related drug interactions.

In fact, the prescribing information for Mektovi states that no clinically important drug interactions have been identified with it, which is an unusually clean interaction profile for a cancer medication. 

Where Cannabis Could Still Play a Role

Cannabis contains over 100 cannabinoids, with THC and CBD being the two most relevant medicinally. The main interaction concern with cannabinoids, particularly CBD at higher doses, is that they can inhibit certain liver enzymes, including some CYP450 enzymes and, in laboratory studies, UGT enzymes.

Since binimetinib depends on UGT1A1, there is at least a theoretical possibility that a high-dose CBD product could slow its breakdown somewhat, though this hasn't been demonstrated in clinical studies and isn't a documented problem.

Overlapping Side Effects to Watch For

Beyond enzyme interactions, the more practical consideration is additive side effects.

Binimetinib commonly causes fatigue, nausea, dizziness, and vomiting, and cannabis (especially THC-containing products) can cause drowsiness, dizziness, and changes in blood pressure or heart rate. Together, those effects can stack, so if you do use cannabis, pay attention to how you feel, avoid driving when impaired, and be careful standing up quickly.

Many people undergoing cancer treatment use cannabis for appetite or nausea, and oncology teams are generally used to this conversation, so being upfront about the product, dose, and how often you use it lets them monitor you properly.

Final Words

Overall, cannabis isn't known to significantly interact with binimetinib, but the combination hasn't been well studied, so it deserves a conversation with your oncologist or pharmacist.

Let your care team know exactly what you're using so they can keep an eye on things but again, as it relates to the specific drug combination you asked about, they seem to not interfere with each other.

Feel free to reach back out if you have any other questions. We're always happy to help.