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What Causes A False Negative For Morphine In A Urine Test?
Question: if a urine test was givin on 3-31-16 at 3:30pm and not received by the testing lab till 4-6-16 could that cause the false-negative I got for morphine sulfate and or alprazolam? the morphine should both positive and negative? I take 2 60mg 2x a day and .5mg of alprazolam 3x a day. been on this regiment for 9 yrs.
Brief Answer:
I would recommend as follows:
Detailed Answer:
Hello!
Welcome and thank you for asking on HCM!
I carefully passed through your question and would explain that this may lead to a false negative test.
You should know that two common potential causes for false-negative opiate tests are using the wrong test for a specific opiate and having an insufficient concentration of an opiate in the sample.
There are two main tests for this purpose: EIA testing and GC-MS testing.
The second is more specific and is used to differentiate the false positive or false negative tests resulting from EIA testing.
I recommend repeating the urine test again, with urine brought to the lab within 4 hours after urinating and perform both above mentioned tests.
Kind regards,
Dr. Iliri
I would recommend as follows:
Detailed Answer:
Hello!
Welcome and thank you for asking on HCM!
I carefully passed through your question and would explain that this may lead to a false negative test.
You should know that two common potential causes for false-negative opiate tests are using the wrong test for a specific opiate and having an insufficient concentration of an opiate in the sample.
There are two main tests for this purpose: EIA testing and GC-MS testing.
The second is more specific and is used to differentiate the false positive or false negative tests resulting from EIA testing.
I recommend repeating the urine test again, with urine brought to the lab within 4 hours after urinating and perform both above mentioned tests.
Kind regards,
Dr. Iliri
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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