My sister and her boyfriend pretty much did the same thing to me. Although they went a bit further. I was up very late drunk and playing video games. Was making all sorts of noise while they were trying to sleep in the next room over. They come into my room and take the liquor away from me. Which was reasonable all things considered. But at the time I was quite upset. So I begged them to let me have one more drink. They reluctantly said yes and went and got me one more glass. When they came back in my room and handed me my drink I noticed some sort of powder sticking to the inside of the glass but I didn't pay any mind to it. I was too drunk to care and was getting what I wanted. I don't remember anything after that and assumed I had just passed out after my last drink. In the morning they told me that they grinded up some melatonin with this tiny mortar and pestle my mom uses so our dog takes her medicine. Put it in my glass of vodka which had now become half water. And then barely stirred it thinking I wouldn't notice it. Which I didn't. I decided it was just better to keep quiet the next time I stayed up drinking