I'm just wondering, if you take ambien (zolpidem) for a long time, can it cause depression or other side effects?

No depression, but..: I am not aware of any studies indicating a correlation between chronic zolpidem use and major depression. Some patients have become physically dependent on the medication; some develop tolerance (i.e. They need to increase their dose over time); some pts have memory impairment, usually while the med. Is in their system; and some have had episodes of sleepwalking or doing other purposeful behavior.