How Does Alcohol Affect THC Blood Concentration?

If you’re the type of person who likes having a beer in one hand and a joint in the other, you may be interested in this new study from the American Association of Clinical Chemistry (AACC), which found that THC blood concentrations increase significantly with alcohol consumption.

Most of us are experientially familiar with the effects of pairing marijuana with drinks, but not a lot of research has been done on what’s actually happening physiologically speaking. This particular study had a small sample size of just 19 people, but it does provide a jumping-off point for future research on how the two interact. They tested variations of small and large doses of cannabis and alcohol, and compared them with control and placebo groups. Without alcohol, THC concentrations fell between 32.7 and 42.2 µg/L THC with low and high doses respectively, and with alcohol, those amounts increased to 35.3 and 67.5 µg/L THC.

These figures may not mean much out of context, but the jump in THC concentration is a notable one. In their press release, the researchers mention the implications these results may have on the drafting of DUI laws, which have been a point of contention among marijuana users as it is more difficult to measure impairment with cannabis than with alcohol. This beast of a topic warrants a longer discussion (oh hey, like this one here), but at the very least, it’s good to see that research is being done in this area; those who’ve witnessed the implementation of arbitrary per se cannabis DUID limits know it’s sorely needed. But really, you don’t need empirical evidence to know that consuming alcohol, cannabis, or a combination of the two requires a degree of responsibility when driving is involved.