Hang in there. I've been on Lexapro for a couple of months now, and I LOVE it.

I switched from Wellbutrin to Lexapro, so I don't know if it was the Lexapro kicking in fast or the Wellbutrin being out of my system, but I felt lots better pretty quickly. Give it at least a week, even two, to get a feel for how it's going to work for you. It's going to take a month to reach it's full effect. I'm almost 100% certain it was the Wellbutrin being gone that calmed me down so quickly. Raving banshee is an understatement for how that drug left me feeling.

I don't know about klonopin side effects, but I'd at least try one if I didn't have to be alert for the next several hours. Especially since it sounds like your doc is only doing it short term until the Lexapro gets better established in your system.