4 doctors weighed in:

How could i show cannabis in my urine test when it has been 20 years since i last smoked pot? I recently had to take a urine test for drugs. It showed my use of prescribed oxycodine and cannabis. I haven ot smoked pot for over 20 years. I have not injeste

4 doctors weighed in
Dr. Alan Wartenberg
Addiction Medicine
2 doctors agree

In brief: It shouldnt

Was the test a screening test or was it confirmed? Screening tests have lots of false positives - many of the drugs used in treating arthritis (like ibuprofen) can cause false positives.
If it was confirmed with an appropriate technique (like gc/ms), those positives should be proven to be false. There are also mistakes in labeling the sample either when collected or tested. Demand a repeat test.

In brief: It shouldnt

Was the test a screening test or was it confirmed? Screening tests have lots of false positives - many of the drugs used in treating arthritis (like ibuprofen) can cause false positives.
If it was confirmed with an appropriate technique (like gc/ms), those positives should be proven to be false. There are also mistakes in labeling the sample either when collected or tested. Demand a repeat test.
Dr. Alan Wartenberg
Dr. Alan Wartenberg
Thank
Dr. Matthew Bressie
Family Medicine
1 doctor agrees

In brief: Thanks

Thanks for your question.
It sounds like you had a drug screen but there may not have been a confirmatory test ordered. Even taking Ibuprofen can make a urine drug screen positive for cannabis. The advantage to the simple screen is it's speed and the fact that it can be done on site - the additional test to make sure it's actually cannabis and not a false positive must be sent to the lab and takes more time. To have a truly positive screen for cannabis, you must have either eaten something with marijuana in it or smoked marijuana. The "screen and confirm" test is designed not to be positive with incidental exposure (standing next to someone smoking marijuana, for example.) you could request a formal drug screen and ask that it be ordered "screen and confirm" to make sure this wasn't a false positive.

In brief: Thanks

Thanks for your question.
It sounds like you had a drug screen but there may not have been a confirmatory test ordered. Even taking Ibuprofen can make a urine drug screen positive for cannabis. The advantage to the simple screen is it's speed and the fact that it can be done on site - the additional test to make sure it's actually cannabis and not a false positive must be sent to the lab and takes more time. To have a truly positive screen for cannabis, you must have either eaten something with marijuana in it or smoked marijuana. The "screen and confirm" test is designed not to be positive with incidental exposure (standing next to someone smoking marijuana, for example.) you could request a formal drug screen and ask that it be ordered "screen and confirm" to make sure this wasn't a false positive.
Dr. Matthew Bressie
Dr. Matthew Bressie
Thank
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