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What Causes Negative Urine Test Result And Positive Oral Swab Result For Cocaine?
Question: Our son is being tested weekly by urine and swabs how could it be possible that his urine tests are negative to cocaine and his oral swabs test positive? He denies ever using cocaine and something doesn't seem right. He now has to have a hair test done since we have been testing him at home and our tests prove negative as well. I would like to know IF there is anything he could be using in his mouth or how sensitive him being in contact with the drug that it can be negative in urine and positive in an oral swab. Also, if he has not ingested cocaine willingly will that prove positive in a hair test. I do not know how a hair test is done, but if the kid is not taking the drug on his own then what possibly could cause an oral swab positive test?
Brief Answer:
This is not typical
Detailed Answer:
Hi and thank you so much for this query.
My first worry is why your son is being tested repeatedly for drugs? Has he committed a crime or has he been into drugs before for these measures to be applied? And the seriousness with which he is being tested is also of concern to me.
Mouth swab tests are rapid and provide instant results. In a few cases, the test can return positive if he is taking some oral medications that may interfere with the results. If he is on any medications, please let me know so that I can assess to see if it is susceptible to cause false positive tests.
I will not be surprised the oral swab tests could just be getting it wrong all the times with repeated testing. If you have the chance, please request a different brand/manufacturer to be used when he next goes for testing.
It would be extremely rare for mouth swab testings to be positive and urine not unless he just ingested the drug and it has not had the time to make its way to the urinary system. This is clearly not the case and am not sure why he has this.
A hair test is a more robust way to screen for drug abuse. It can show positive results for up to 90days after drug ingestion. It consist in plucking of some hairs and analyzing them. This is used because drugs are excreted in hairs and it takes about 90days for a hair to grow and fall off completely.
In any case, stay calm. Follow up with the health authorities and see what the subsequent testings come up to be. If they suggest that your son takes drugs, please talk with him and hear what he has to say. Advice him to be honest and sincere as it would be of great help knowing whether he takes drugs or not.
I hope this addresses your query fully. I wish you well. Thank you so much for using our services and do feel free to ask fr more information if need be.
This is not typical
Detailed Answer:
Hi and thank you so much for this query.
My first worry is why your son is being tested repeatedly for drugs? Has he committed a crime or has he been into drugs before for these measures to be applied? And the seriousness with which he is being tested is also of concern to me.
Mouth swab tests are rapid and provide instant results. In a few cases, the test can return positive if he is taking some oral medications that may interfere with the results. If he is on any medications, please let me know so that I can assess to see if it is susceptible to cause false positive tests.
I will not be surprised the oral swab tests could just be getting it wrong all the times with repeated testing. If you have the chance, please request a different brand/manufacturer to be used when he next goes for testing.
It would be extremely rare for mouth swab testings to be positive and urine not unless he just ingested the drug and it has not had the time to make its way to the urinary system. This is clearly not the case and am not sure why he has this.
A hair test is a more robust way to screen for drug abuse. It can show positive results for up to 90days after drug ingestion. It consist in plucking of some hairs and analyzing them. This is used because drugs are excreted in hairs and it takes about 90days for a hair to grow and fall off completely.
In any case, stay calm. Follow up with the health authorities and see what the subsequent testings come up to be. If they suggest that your son takes drugs, please talk with him and hear what he has to say. Advice him to be honest and sincere as it would be of great help knowing whether he takes drugs or not.
I hope this addresses your query fully. I wish you well. Thank you so much for using our services and do feel free to ask fr more information if need be.
Note: In case of any other concern or query related to prevention, evaluation, diagnosis, treatment, or the recovery of persons with the any type of addiction or substance use, follow up with our Addiction Medicine Specialist. Click here to book a consultation now.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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