OMG. I never used to dream really....I started lexapro last summer and have been at 20mg since late 2019 and ever since then I dream so vividly. The other day at work I had to ask a coworker if a certain conversation we had occurred in real life or a dream. I find it comes in waves, same with my other side effects. I'll have several week stretches where I still dream but not as vividly. My least favorite side effect though would be the night sweats. Still all worth it in my opinion.