I think valium and xanex's half life is over 20 hours. Ambien and sonata are much better choices for sleep. Also valium is addictive as hell and if you are taking 50mgs at a time you will start doing things you do not remember doing, if you have not already. I used to take loads of benzos, vals, xans, kolonipin ect. and I started running into people who knew me but I couldn't remember talking to. Also I was in law school at the time and I started forgeting everything I was reading. Pretty bad shit if you take too much. My buddy got two dui's on vals. He registered 0 on the breathalizer but could barely stand up so the cop arrested him. A few days later it happened again. There are much better ways to put yourself to sleep.