Valium
Just a suggestion, but if you are taking for sleep aid, then you should just take Melatonin.
It is over the counter, and if you use 5-10mg's, depending on your body composition, you should be fine in a half hour or so.
I used to take ambien and then tried valium and xanax and was told by a friend to try Melatonin at 3-6mg's per night. It took me 9 mg's to get to sleep, so now I buy the 5 mg tablets and take two. 1/2 hour later, I am out and it is not hard to wake up the next morning.
Melatonin is cheaper, non addictive and safer to use.
Just my two cents.
macster