A licensed doctor can prescribe Valium (diazepam) if he feels the medication is appropriate for you based on your medical problem, other medication you take, and your medical history. Valium is...
Nope - both contain Benzodiazepine, which is what the drug test keys on. I disagree with above you will test positive for benzodiazepine which both have they will not be able to tell the difference.
That doesn't seem very safe. Adderall reacts badly with Diazapam (Valium) but I'm not sure about the Vicodin though, I'm sure you will be fine with that. You might want to talk to your doctor about...