I understand that beer 3.2% alcohol will stay in your urine 24hrs? Where as any narcotic prescribed drugs will be observed in your urine for 3 days 72hrs. Is this close to being accurate?

It depends on your body weight, your gender, and many other things.

If you're undergoing drug screening of any kind the only sure way to get a clear test, is to not drink or do drugs. If you're undergoing drug screening then there's a reason for it.

So, why would you risk it when you're not supposed to? Why are you not getting help for this addiction instead of worrying about a test after you've done the deed?

An ounce of prevention is worth a pound of cure.

I understand that beer 3.2% alcohol will stay in your urine 24hrs? Where as any narcotic prescribed drugs will be observed in your urine for 3 days 72hrs. Is this close to being accurate?

No it isn't. One beer as described would have a BAC clearance around 1.5 - 2 hours. Of course any substance remains detectable in urine until you void.

Drug clearance is based on drug type, your metabolism for the specific drug and history of use.