So my character was moaning like a bitch after a baseball game with a zombie and I decided to apply some alcohol to my wounds. I had no UI messages (bleeding, hunger, thirst, etc).
However, when I applied to wounds (I know I didn't drink it), I got a yellow "sick" indicator in my inventory. I got a few messages of "my wounds hurt less" and then the "sick" thing died.
I've tried this twice and have some pics I can upload if needed. Both times it did the same thing.