I've been on Lexapro since December. My dosage is REALLY low - I started out at 10 mg., but it made me very tired and almost lethargic. So my doctor cut the dosage in half and it's been WONDERFUL!! No side effects that I can think of once it gets in your system. I take it in the a.m. If you take it for 3-6 weeks, and you're feeling "blah", let your Dr. know. Your dosage may have to be altered.
One good thing.......I've lost weight. I put myself on a diet before I started taking it, since I knew from experience that antidepressants can cause weight gain. I've lost almost 22 lbs., so that's been a huge plus, along with no more depression!!