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Can Terbinafine Cause False Positive Result For THC In Blood?
Question: Can terbinafine cause a false positive thc in a blood sample
Brief Answer:
not one of the known medications
Detailed Answer:
HI, thanks for using healthcare magic
There are some medications that can cause false positive results but this is not one of the medications known to have this effect.
The medications that can cause false positives are: ibuprofen, naproxen, ketoprofen, piroxicam, , pantoprazole, promethazine
These are the more common ones, others would be dronabinol, sulindac
If he is using any of these medications then it is possible that it had an effect.
After the initial screening test, it is possible to get more in depth blood tests called GC-MS, that can correctly identify if the positive result is due to using medications or illegal substances.
I hope this helps , feel free to ask any other questions
not one of the known medications
Detailed Answer:
HI, thanks for using healthcare magic
There are some medications that can cause false positive results but this is not one of the medications known to have this effect.
The medications that can cause false positives are: ibuprofen, naproxen, ketoprofen, piroxicam, , pantoprazole, promethazine
These are the more common ones, others would be dronabinol, sulindac
If he is using any of these medications then it is possible that it had an effect.
After the initial screening test, it is possible to get more in depth blood tests called GC-MS, that can correctly identify if the positive result is due to using medications or illegal substances.
I hope this helps , feel free to ask any other questions
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thank you
My son had to have a blood test prior to commencing the course of medication and will be having a second after 3 months due to the affect the medication can have on the liver. Although you say that Terbinafine will not cause a false positive, can it affect the efficiency of the liver function sufficiently to make him retain or not process the cannaboids and therefore the thc level may be kept artificially high or at least take less time than normal for the thc level to drop.
Regards
My son had to have a blood test prior to commencing the course of medication and will be having a second after 3 months due to the affect the medication can have on the liver. Although you say that Terbinafine will not cause a false positive, can it affect the efficiency of the liver function sufficiently to make him retain or not process the cannaboids and therefore the thc level may be kept artificially high or at least take less time than normal for the thc level to drop.
Regards
Brief Answer:
relates to breakdown products of medication, if they r similar to what test
Detailed Answer:
HI
Terbinafine can potentially affect the liver in some persons but not usually to the extent of causing false positive drug reactions.
The false positive reactions normally occur when a drug that is being used causes similar end products or break down products that are being tested for.There is a cross reaction.
The drug tests look for specific products. It is not related to the break down on terbinafine specifically only if the terbinafine was broken down into metabolites that may cross react with those seen when THC is broken down.
If you wish I can refer you to 2 medical sites that discuss and list the medications that can cause false positive reactions- (1)medscape or emedicine- this is a medical website used by doctors for medical information. It actually only lists the pantoprazole but another site mentions the other products
(2)dig.pharm.uic.edu
Please feel free to ask any other questions
relates to breakdown products of medication, if they r similar to what test
Detailed Answer:
HI
Terbinafine can potentially affect the liver in some persons but not usually to the extent of causing false positive drug reactions.
The false positive reactions normally occur when a drug that is being used causes similar end products or break down products that are being tested for.There is a cross reaction.
The drug tests look for specific products. It is not related to the break down on terbinafine specifically only if the terbinafine was broken down into metabolites that may cross react with those seen when THC is broken down.
If you wish I can refer you to 2 medical sites that discuss and list the medications that can cause false positive reactions- (1)medscape or emedicine- this is a medical website used by doctors for medical information. It actually only lists the pantoprazole but another site mentions the other products
(2)dig.pharm.uic.edu
Please feel free to ask any other questions
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Hi Doctor
Thanks for your prompt reply. It wasn`t so much the false positive, I suppose the question is this. If my son has used cannabis, would using Terbinafine cause the liver to perhaps not process things as efficiently and therefore not rid the body of the thc as quickly ie delay the body in reducing levels of thc in its cleansing process.
Regards
XXXXX
Thanks for your prompt reply. It wasn`t so much the false positive, I suppose the question is this. If my son has used cannabis, would using Terbinafine cause the liver to perhaps not process things as efficiently and therefore not rid the body of the thc as quickly ie delay the body in reducing levels of thc in its cleansing process.
Regards
XXXXX
Brief Answer:
if function very impaired can have an effect
Detailed Answer:
HI
If there is significant impairment of his liver function then it could have an effect.
It would depend on how often the cannabis is used.
In persons with no problem with metabolism/break down of the cannabis, with one time use- can be detected in the blood after 12 to 24 hours, in the urine 1 to 7 days. Not likely detectable in the hair after one time use
With repeated use, in the blood for 2 to 7 days, urine 7 to 100 days , in the hair for months.
In persons with problems with breakdown of the cannabis, these time periods would be extended but it would not be possible to definitely say by how much.
It would normally require significant impairment of metabolism.
His liver function blood tests would show if his liver function is significantly impaired enough to affect this
If anything else unclear, feel free to ask
if function very impaired can have an effect
Detailed Answer:
HI
If there is significant impairment of his liver function then it could have an effect.
It would depend on how often the cannabis is used.
In persons with no problem with metabolism/break down of the cannabis, with one time use- can be detected in the blood after 12 to 24 hours, in the urine 1 to 7 days. Not likely detectable in the hair after one time use
With repeated use, in the blood for 2 to 7 days, urine 7 to 100 days , in the hair for months.
In persons with problems with breakdown of the cannabis, these time periods would be extended but it would not be possible to definitely say by how much.
It would normally require significant impairment of metabolism.
His liver function blood tests would show if his liver function is significantly impaired enough to affect this
If anything else unclear, feel free to ask
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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