insomnia
"I have taken Ambien, on and off, for several years. I have bipolar disorder, resulting in a chronic sleep problem. 10 mg/day works well for a few months, then I become habituated. I have tried increasing to 20 mg/day, but I eventually become habituated to that dose as well, and neither I nor my doctor will go to a higher dose. Nothing else works as well, so I usually struggle along for a couple of months, then go back to 10 mg/day of Ambien. The other problem I've seen is that I CANNOT  mix it with alcohol. I learned the hard way. I had "waking blackouts" after I'd had a couple of drinks. People told me of things I'd done, of which I had no memory of. "