They also perform the drug test to check the volume of a certain drug to make sure you are receiving the correct amount.
They can tell HOW much you are taking as well with the drug tests. It can not only tell you don't have any in your system, but the levels. They can tell if you aren't taking enough or too much.
As others have said, the pain management Dr's are under huge scrutiny for dosing out narcotics. They have to drug test and pill count since they dose so many scrips nowadays. Even if you aren't taking them and selling them, they can tell by your pee test what and how much you are or are not taking. And vice versa that if you are taking more than what is prescribed, it will show up in your system too. You can't fool them borrowing someone elses scrip for a count. Your pee will tell the truth on you.
It is also done to find out if you are possibly selling them, or in my former case, using them too fast. I came in, had a clean drug test, and was dumped by my doctor in March of 2012. Best thing that has happened to me in a long time, the big kick to get me clean.
Bryan
And also to make sure your not on other drugs....I was tested my first day before I even received a script.... the question I have to ask is why are you taking more than prescribed? What is the reason you are prescribed them?
Most doctors test their narc patients to make sure they are taking the meds instead of selling them to others. It has become a huge problem for them