Weed is easily diluted in tests lol...
Chug down tons of water on the day of the test, avoid any exercise. Make sure you are pissing crystal clear before you go, then on your way there, take an aspirin, a vitamin, and a vitamin b6 with another bottle of water. Supplement with creatine throughout the day as well, taking high dosages. Creatine's byproduct, creatinine, is checked in most common drug tests because it is usually drained if you are diluting, so basically you will fail the test and be labeled as a "dilute" if you do not supplement with creatine and vitamins and such, to ensure your piss appears natural, while in reality it is extremely diluted.
As for your valium, I have no clue. I'd never pop prescription pills that were not prescribed to me.
Haha good luck with that. Tests have gotten better.
Listen it all depends on the level of testing.
For my NYS Drug test, I am tested for anything and everything. Including a test for shrooms(which is a special separate test). However, for my regular work test, its the basic run of the mill test...
Now were assuming your just going to get a urinalysis...
This is what a basic and most common test includes
1. Cannabinoids (marijuana, hash)
2. Cocaine (cocaine, crack, benzoylecognine)
3. Amphetamines (amphetamines, methamphetamines, speed)
4. Opiates (heroin, opium, codeine, morphine)
5. Phencyclidine (PCP)
Now, there are also expanded tests. People have to pay more for these, and they are added onto a regular test, not included.
1. Barbiturates (Phenobarbital, Secobarbitol, Butalbital)
2. Hydrocodone (Lortab, Vicodin)
3. Methaqualone (Qualuudes)
4. Benzodiazepines (Valium, Xanax, Librium, Serax, Rohypnol)
5. Methadone
6. Propoxyphene (Darvon compounds)
7. Ethanol (Alcohol)
8. MDMA (Ecstasy)
There is another test, but I have never ever seen it used except for when I applied for Security clearance through the government...
Valium is detectable up to 40 days. If your a heavy user, expect it to last that long.