Hi! Dreams as such have no direct relationship with antidepressants or other medications. Everyone will have dreams while asleep; some people do not feel or remember them next day. Lexapro may be the indirect cause, because all antidepressants alter sleep architecture, so that people who never remembered their dreams before, will start remembering them. Otherwise dreams are truly a reflection of what your mind experiences subconsciously throughout the day.
Next Steps
Try to relax before going to sleep and do not take any beverages.
Health Tips
If the problems persist, you may try melatonin tablets under guidance of a doctor.