Another way to drug test is oral drug testing.  This procedure involves placing a device in the clients mouth to test their saliva.  This is a good alternative to urine testing.  If the client says they can’t “go”, then you can use the saliva test.  If someone knows they are going to be positive for a drug, they will say they can’t go to avoid testing positive.  There is also a medical diagnosis called “shy bladder”, where a person can’t urinate because they are being watched or asked to urinate.