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Ask Dr. D. Love Your Own Question
Dr. D. Love
Dr. D. Love, Doctor
Category: Drug Testing
Satisfied Customers: 18458
Experience:  Family Physician for 10 years; Hospital Medical Director for 10 years.
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I'm 65 years old and flunk a drug test. I haven't touched

Customer Question

I'm 65 years old and flunk a drug test for cocaine. I haven't touched cocaine well over 30 years ago. What could cause the failure? I do have sever rhumatord artritis.
Submitted: 1 year ago.
Category: Drug Testing
Expert:  Dr. D. Love replied 1 year ago.

Hello from JustAnswer.

You do not say what type of test was done, but the most likely scenario in someone that has not used cocaine is that you had a screening drug test done that had a false positive. The screening tests are very convenient, but the tests have a fair amount of false positives, and the reason for many of the false positives are never known. The usual approach to identify whether the screening test is a false positive is to order a confirmatory test, such as gas chromatography/mass spectrometry, or GC/MS. You should insist that a confirmatory test be done on the urine sample. If the confirmatory test is negative, then that is proof that the screening test was a false positive, and no further evaluation is needed.

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Customer: replied 1 year ago.
The test was confirmed. For some strange reason it took 5 weeks to come back. What could possibly cause it to be positive? Also what percent of testing is wrong? Do these test hit 100 percent?
Customer: replied 1 year ago.
The test was confirmed positive. It was some what strange it took 6 weeks for the confirmation. What could possibly cause this test to be positive? Also what percentage of test can be wrong?
Expert:  Dr. D. Love replied 1 year ago.

There is no test that is 100%, but the confirmatory test is the gold standard and is quite close, and when the tests is inaccurate, it is that it may miss a drug that is present, rather than incorrectly identify a drug that is not present. The only realistic cause of a false positive on a confirmatory test is from laboratory error, such as confusion or mislabeling of specimens in the lab, which in a certified lab is extremely unusual. The proof of the rare lab error would require testing the same specimen in a different lab, which would be impossible after 5 weeks.

The other possible cause of a true positive in someone that has not intentionally taken a drug is that the person was given the drug without their knowledge.

Customer: replied 1 year ago.
I'm confused about the 5 week statement. It was sent to another lab could you please explain that better.
Expert:  Dr. D. Love replied 1 year ago.

The confirmatory test is a specialized test that apparently could not be done in the original lab that did the screening test, so that the specimen was then sent to the specialized lab. It does not take 5 weeks to do the confirmatory test, nor does it usually take 5 weeks to transport the specimen, so a 5 week delay usually also indicates that there was some backlog at the specialized lab to do the confirmatory test. As long as the specimen was properly stored, there would not be any issues with accuracy of the test itself because of a 5 week delay, although there is a potential for mishandling or mislabeling of the specimen at every handoff of the specimen.