There are some medications that cause vivid dreams, night terrors, and even hallucinations. Often they lessen or disappear after a few weeks. I'm surprised that the Lexapro didn't seem to help rather quickly (much shorter time than other ssri's/ ssnri's. Perhaps it isn't "just" the medication..but holiday stress added in? Extremely stressful times can cause delusional thinking, etc.. coupled with a new med that also affects that area of the brain, and who knows?

I would personally think about cutting the dose of the original med, and see if the negative effects lessen also? There might also be a difference between an extended release med and regular one (same med) affects someone.

If he is really frustrated, a little extra information on the complexity of the brain, it's chemicals and all that is background to the meds, might help? I know it's difficult when depressed, but good, solid information can help us be more patient at times. TC