Answer:
Mixing opiates with Valium is a good way to get dead. A cause of death called "multiple drug intoxication" is what you'll find on the death cert. I lost two good friends to that...they were mixing hydrocodone with diazapam (Valium). It's a crap shoot. If you get the levels high enough, you stop breathing in your sleep.
I am just adding on to a very smart persons answer, I just lost my best friend of 20 years THAT WAS NOT A DRUG USER from the same thing. Doesn't have to be very much. Don't mix scripts
I am a nurse and have had many surgeries. After surgery I was prescribed Valium and Vicodin to take together. It managed my pain very nicely and I had returned to work already. I did not abuse this and followed the surgeon's orders to the letter.
I agree that you should not take or mix medications without a physician's order.