insomnia
"Without Ambien I'm up literally all night. But if you don't take it on am empty stomach it doesn't work at all. I take it at midnight and can't eat after 5 or 6PM or else it won't work. If you try and stay up after it starts to work you may do things you wouldn't normally do - like shop online, which I've done and many people I know. Luckily everything I've bought is stuff I've wanted, but still..."