How Does Cannabis Interact with Other Drugs?

Does it?

Virtually all chemical compounds, from over-the-counter drugs and prescription pharmaceuticals to illicit substances, interact with other compounds. There are, for example, 82 identified drug interactions with caffeine (of which 25 are classified as moderately severe to severe). Even seemingly benign substances, like grapefruit, are known to interact with many prescription drugs. When it comes to cannabis, most potential interactions that have been identified are relatively mild. And, in fact, some drugs seem to work together with cannabis favorably.

But, before we dive deep on some of the most common drugs people combine with cannabis, it’s important to understand the difference between an “additive” and “synergistic” effect. Additive simply means the interaction between two chemicals equals the sum of their parts (e.g. 1+1 = 2). Synergistic means that when two chemicals interact, the effect is greater than the sum of their parts (e.g. 1+1 = 3. Sounds like “alternative math!”). Likewise, keep in mind that THC/CBD ratios and different strain profiles (with variable cannabinoid and terpene profiles) can influence effects.

Note: in some cases, cannabis may actually increase the effectiveness or potency of other drugs. But, even if the interaction is potentially beneficial, close monitoring by a medical professional, along with regular blood work, is important as a patient may need adjust their dosing accordingly.