First off, xanax and valium are benzos, not barbiturates. Benzos are supposedly safer. But anyway, the withdrawal picture is basically the same....your body gets so "overstimulated" due to the removal of the drug that you can suffer a stroke, heart attack, seizure, suicidal tendency, and lots more stuff. So yes, you can die either directly or indirectly. The actual withdrawal is different for everyone and has alot to do with the amount of drug being taken and then stopped.
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