I've been on Lexapro since June. I have no problems now and take it in the morning. When I first started I had trouble staying awake during the day. I switched to night, it didn't help.
I've always been sensitive to meds, so I take it slow and ramp up. I eventually took a 1/2 for 2 weeks. Then 1/2 twice a day for another couple weeks. I was finally able to take the whole pill after about 6 weeks of trial and error. I don't notice any effects today and it sure improved my outlook on life.
Much luck to you.