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What Causes Differnt Result For Cocaine In Urine And Oral Swab Tests?
Question: Our son is currently being tested with urine and oral swab. How is it that his urine's are negative for cocaine, but oral swab tests positive? And he has denied doing cocaine and wants to figure out what could cause this to happen?
He is now being court mandated to get a hair test done for cocaine and I need to understand how that works and if he is coming into contact, but not using the drug how sensitive and what could cause the oral to be positive and not the urine
I was also wondering that if he is not using cocaine, even with the oral swab being positive, is that something the hair test can confirm? I am at a loss making myself understand this situation. Thank you
He is now being court mandated to get a hair test done for cocaine and I need to understand how that works and if he is coming into contact, but not using the drug how sensitive and what could cause the oral to be positive and not the urine
I was also wondering that if he is not using cocaine, even with the oral swab being positive, is that something the hair test can confirm? I am at a loss making myself understand this situation. Thank you
Brief Answer:
Lab testing with Hair is better at this stage
Detailed Answer:
Hi,
It is difficult situation to analyze. As per my understanding any immunoassay (instant) test could be false positive, however the false positivity rate defers from test to test. I think the oral swab test was based on immunoassay technology.
Now they would do a lab test which has very less false positive rates. It uses Gas chromatography/Mass spectrometry technology. Cocaine testing has far less false positives than other drugs. So if it proves on hair test then it is next to impossible to prove its false positivity on scientific basis. You should ask your son if someone slipped cocaine without his knowledge.
Hope this helps.
Lab testing with Hair is better at this stage
Detailed Answer:
Hi,
It is difficult situation to analyze. As per my understanding any immunoassay (instant) test could be false positive, however the false positivity rate defers from test to test. I think the oral swab test was based on immunoassay technology.
Now they would do a lab test which has very less false positive rates. It uses Gas chromatography/Mass spectrometry technology. Cocaine testing has far less false positives than other drugs. So if it proves on hair test then it is next to impossible to prove its false positivity on scientific basis. You should ask your son if someone slipped cocaine without his knowledge.
Hope this helps.
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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