When my dose of lexapro (escitalopram) was too high, i got arrogant. is that a normal side effect?

I may have been: related to being more agitated, which often takes the form of intolerance. That's just a guess, but I've seen this more than once. The antidote is to visit your prescribing MD and put the question to him/her. No, usually this is not a common side effect. For a list of SSRI/SSNRI side effects, go to the NIMH website, or even Psychology Today. Wikipedia isn't actually too bad (but consider.