I got a free sample from my college when I bought stuff from our on-campus bookstore. I was feeling tired one night and had a date planned, so before my date got to my house, I took the Vivarin. I was very awake, but during our date I had to go to the restroom twice. And ended up puking the second time. I felt nauseous the whole time and we had to leave our date and he brought me home. It was horrible.