CBD & Drug Interactions

CBD & Drug Interactions

Most compounds, over the counter medication to illegal drugs, interact with other chemical makeups. Even grapefruit is known to interact with prescription medication. So, it is prudent to realise CBD will interact with some medications. Most potential interactions are very mild, and some drugs are found to mostly work very well with CBD. 



CYP450 Enzyme

This is where CYP450 comes into play. It is an enzyme system found in the liver, and is responsible for metabolizing toxic compounds/medicines you take orally, with it processing over 60% of anything you have taken.  

The Cytochrome P450 can increase the time for some drugs to metabolize, with CBD inhibiting the P450. CBD is not alone in doing this though, with St John’s Wort, grapefruit, watercress and goldenseal behaving in a similar manner.  

Medications and drugs known to use the CYP450 (enzyme system in the liver) are: –  


HMG CoA reductase inhibitors 

Calcium channel blockers 



HIV antivirals 

Immune modulators 








Beta blockers 



Angiotensin II blockers 

Oral hypoglycaemic agents 


This list does not include all of the potential medications impacted by cannabidiol. Nor will every medication in the categories contained on this list cause an interaction.  


Insulin Resistance

There is evidence to suggest that CBD may decrease insulin resistance, improve the metabolic process and improve blood sugar control. There could also be a risk that cannabis, combined with other drugs, could lower glucose levels too much. However discussing things in full with your medical specialist/GP is your best bet, if looking into this further.  


CBD may also increase the effect of blood thinners, or drugs known to carry the risk of blood thinning. (Warfarin, Ibuprofen, Naproxen etc) by slowing down the metabolism of the drugs taken.  


The interplay between CBD and P450 seems most prominent when it comes to epilepsy and anti-seizure medications. It has been found that CBD elevates blood concentrations of clobazam (an anticonvulsant) in people, while elevating norclobazam (an active metabolite of clobazam). Which leads to a straightforward remedy of reducing clobazam which also reduces side effects. So, this can be a good twinning for CBD. Again, working with the knowledge and input of your GP/specialist etc.  


Many medical professionals have come forward to suggest cannabis (as an alternative pain medication) could play a role in stemming the overuse of prescription (and illicit) opioids. Opioid’s and CBD taken together have also proved to work well for pain relief. It certainly helps my chronic pain symptoms. 


CBD & Caffeine

The biggie for me is caffeine! And luckily for me, and all you lot. CBD and coffee go very well together as caffeine is molecularly very similar to adenosine which is a compound produced in our bodies that activates the A2a receptor. Caffeine binds to the A2a receptors, inhibiting the reuptake of adenosine. 


As adenosine binds to the A2a receptor The result is what is commonly known as the ‘rest and digest’ effect. So by blocking adenosine from binding it ends up in vasodilation, increased clarity and alertness. 


CBD is also a partial agonist of the A2a receptor, so the theory goes that by combining caffeine and CBD, adenosine is blocked across the board, resulting in not only more stimulation, but reduced anxiety (due to CBD’s effects on other neurotransmitters systems). 


Additionally caffeine is metabolized by a CYP450 enzyme. As CBD inhibits the CYP450 system, a slowed output rate of caffeine will occur so this can mean the effects of the caffeine will be longer and drawn out.  

cbd brew

So, on one hand, CBD and coffee/caffeine together will cause the boost from your morning cuppa. To last all day instead of just a few hours but on the flipside. It’s easy to overdo it and end up wide-eyed in bed when you are trying to go to sleep. 


Therefore, for most people, CBD is safe and relatively risk free and has less risks than other commonly prescribed medications. The therapeutic versatility is that it can reduce the need to combine multiple medications and also the potential of high-risk side effects.


Ready To start Your Journey? Shop now or try our CBD Dosage Calculator