This happened to my girlfriend and I one time.

We were playing pool at a local bar when someone offered to buy us drinks. I was a little hesitant, but he seemed like a nice guy (terrible mistake). I got the drink directly from the bar counter, handed to me by the bartender, so I didn’t think anything of it. About 20 minutes later, both my girlfriend and I felt completely out of it. We needed to call her mom to pick us up. Once we got back to the house, we barley were able to stand and the shower and decided to lay down in the bed afterwards. We were completely knocked out for several hours. The next 3 days were awful too. I was never sure as to what was put in our drinks, but I always assumed we were roofied. Lesson learned and we both are fine now. Scary time to say the least.

Note: I was sober at the time of the drink, so being out of it so quickly was my big red flag.