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Dr. Andrew Rynne
Dr. Andrew Rynne

Family Physician

Exp 50 years

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What causes negative drug urine tests?

Answered by
Dr. Karl Logan

Orthopaedic Surgeon

Practicing since :1999

Answered : 705 Questions

Posted on Fri, 1 Aug 2014 in Brain and Spine
Question: I have spinal bifida, and right leg amputated I have been in a hospital bed since Feb. 2014 ... My doctor gives me pain medication, I have taken them for a couple of years, I had to have a pill count that my in home nurse did and it was accurate.... They took my urine from a straight XXXXXXX next day doctor called said urine was negative I was in shock, then he ordered blood the nurse told me she had the wrong vial they did it again today what would make it not show up... I feel so upset and this is degrading to me I have two large wounds I have in home wound packing also
I take all my pain medicine as directed !!!!!!! And the lab told my Doctor it was not in my Urine !!!! How can that be...... I have been taking the same medicine for over one year I take Ditrapan for my bladder I have to XXXXXXX all the time I am 100% paralyzed
Answered by Dr. Karl Logan 5 hours later
Brief Answer:
Explanation of negative urine test

Detailed Answer:

thanks for clarifying. I'm still a little confused as to why your dr would be testing your urine or blood for the drugs that you are supposed to be taking for your medical condition. this is not usual practice.

there are many causes of a negative drug urine tests when it should be positive including to timing, the amount of fluid that you drink, contamination of the specimen with blood or detergents.

you should also check the drugs that you are taking to ensure that they are what they should be and of the necessary quality. if you concerned ask your pharmacist to replace them.

I hope this answers your question

best wishes
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

The User accepted the expert's answer

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