I am prescribed vicodin 1 to 2 tabs four times a day as needed. I have been able to reduce to only having to take 2 or 3 and when he tested me it was negative. I asked him to also check for a bladder infection and he didnt 3 days after I gave the urine sample I went back to the doctor and was tested for a bladder infection and I did have one. Can a bladder infection or uti cause the drug test to not show the vicodin?