insomnia
"I was prescribed Ambien, then later Ambien CR, for several years for insomnia.  Wow!  Just like I'd heard about -- take the pill and 20 minutes later I was out.  Didn't really experience "hangover" the next day, but then I allowed myself 7 +/- hours of sleep.  Then, it happened:  woke up one morning and my kitchen was somewhat of a mess but I didn't remember being up or making tuna salad on toast.  That happened a few more times before I weaned myself off Ambien.  Haven't had a good night's sleep since.  I've been prescribed a few different sleep meds but haven't had any success.  Tried OTC diphenhydramine (Benadryl, Motrin PM) with Melatonin and began not remembering simple words, appointments, etc."