One of the pleasures of learning foreign languages is to find words which cannot be translated directly into Japanese. The adjective drowsy is one of such words, I think. When you are drowsy, you are basically sleepy. But being drowsy is different from being sleepy in that the former is especially used to denote the sleepiness caused by some sort of medicine or alcohol. I knew this word when I first listened to the music called Stan by Eminem at the age of 14.
I am drowsy now. I went to an izakaya for the first time in some months. I drank a glass of gin and tonic. I get so easily drunk that even a glass of it can make me hilarious and talkative. After that, I enjoyed karaoke with my friend, and I am home now. It seems that some sort of spirit enabled me to get home. But it is spirits that have made me drowsy. I have a lot of things to do before I go to bed. I learned in my early twenties how to beat my sleepiness and get the job done.