I think perhaps you could discuss it with your T first. "Drunk" to me implies quite a lot of alcohol, but there are degrees of intoxication, of course. I have said to my T that I wish I could have a beer before my appointment - that would not make me drunk, not even close, only slightly more relaxed. My T has said that as long as I don't show up intoxicated, and don't make a habit of it, he would have no problems with that, but since I have a morning appointment before I go to work, it's not an option.

So your T might be fine with it - but then again, maybe not, and it's much better to discuss it before you do it, I think.