Hi all. I have a question regarding the mouth swab test. I see a pain management doctor and I have an appointment coming up in a week. I've run out of my Vicodin 7.5's early. He randomly has me take the mouth swab test where you hold the swab in your mouth for a few minutes. The test is to make sure the Vicodin is still in my system. Since I've run out early, I won't show any in my system. My question is this: I have a MS Contin 30mg that I can take the night before my appointment. Will this satisfy the test, or will he be able to tell it's morphine and NOT Vicodin in my system?