I took Lexapro for the first time yesterday. It was horrible. I was exhausted, and my mind felt so foggy. I didn't even take it this morning. I am fully aware that it can take 4 weeks before the medication starts to work, but I just didn't like the feeling that I had. I don't feel that well today either...I am so drowsy, and as soon as I get home from school, I am going right to bed. I woke up in the very early morning (around 4:00 AM), which is something that I never do. That may be the reason why I am so tired.