I was watching some of Jordan Petersons lectures on youtube and he mentioned that alcohol binds to GABA receptors which reduces anxiety (like valium). However in some people it additionally releases dopamine thus making it more addictive for some people than others which I found really interesting. So you can test if it causes a dopamine response for you by measuring your pulse, taking five shots (need to get past the drink drive limit) and then measuring your pulse again in 10mins.
If your heart rate is higher then it suggests a physiological opiate response that develops into dopamine release. I tried it myself and although my heart rate was slightly higher it was only by a few beats aha I’m safe!