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Hi, Someone Who Isn't Me Used Methamphetamine 11 Days Ago
Question: Hi, someone who isn't me used methamphetamine 11 days ago and is wondering if they would pass a urinalysis screening at 500ng/ml? They are a 5'11 male, 240 lbs. Age 27
Hi, someone who isn't me used methamphetamine 11 days ago and is wondering if they would pass a urinalysis screening at 500ng/ml? They are a 5'11 male, 240 lbs. Age 27
Brief Answer:
almost certainly.
Detailed Answer:
Methamphetamine doesn't stay in the body that long. 5 days is about the limit. double that is pretty guaranteed. Additionally, 500 ng/ml is a bit on the high cut off side. Frankly, the person is more likely to have a false positive (decongestants and many other drugs are similar and cross react) than a real one.
almost certainly.
Detailed Answer:
Methamphetamine doesn't stay in the body that long. 5 days is about the limit. double that is pretty guaranteed. Additionally, 500 ng/ml is a bit on the high cut off side. Frankly, the person is more likely to have a false positive (decongestants and many other drugs are similar and cross react) than a real one.
Above answer was peer-reviewed by :
Dr. Prasad
Brief Answer:
almost certainly.
Detailed Answer:
Methamphetamine doesn't stay in the body that long. 5 days is about the limit. double that is pretty guaranteed. Additionally, 500 ng/ml is a bit on the high cut off side. Frankly, the person is more likely to have a false positive (decongestants and many other drugs are similar and cross react) than a real one.
almost certainly.
Detailed Answer:
Methamphetamine doesn't stay in the body that long. 5 days is about the limit. double that is pretty guaranteed. Additionally, 500 ng/ml is a bit on the high cut off side. Frankly, the person is more likely to have a false positive (decongestants and many other drugs are similar and cross react) than a real one.
Above answer was peer-reviewed by :
Dr. Prasad
Brief Answer:
Then it gets... interesting.
Detailed Answer:
Anywhere that does one urine test does many many of them. We don't do the more expensive confirmatory test if the screen is negative. So.... the nature of the question implies the initial test is positive. Mostly this is because someone lied about their use of drugs. In which case the confirmatory test is guaranteed to confirm the use of drugs. This could occur with a false positive in this case. the difference between the 100 and 500 cut off actually isn't all that big a difference. The drug has a half life of about 10 hrs so a 5 fold difference is about 1 day. 10 days is a LOT of time to get rid of the drug. 20 half lives or 2 to the 20th power.
so, lying about the drug use is a big deal. If not lying, then the confirmatory test is one's friend.
Then it gets... interesting.
Detailed Answer:
Anywhere that does one urine test does many many of them. We don't do the more expensive confirmatory test if the screen is negative. So.... the nature of the question implies the initial test is positive. Mostly this is because someone lied about their use of drugs. In which case the confirmatory test is guaranteed to confirm the use of drugs. This could occur with a false positive in this case. the difference between the 100 and 500 cut off actually isn't all that big a difference. The drug has a half life of about 10 hrs so a 5 fold difference is about 1 day. 10 days is a LOT of time to get rid of the drug. 20 half lives or 2 to the 20th power.
so, lying about the drug use is a big deal. If not lying, then the confirmatory test is one's friend.
Above answer was peer-reviewed by :
Dr. Prasad
Brief Answer:
Then it gets... interesting.
Detailed Answer:
Anywhere that does one urine test does many many of them. We don't do the more expensive confirmatory test if the screen is negative. So.... the nature of the question implies the initial test is positive. Mostly this is because someone lied about their use of drugs. In which case the confirmatory test is guaranteed to confirm the use of drugs. This could occur with a false positive in this case. the difference between the 100 and 500 cut off actually isn't all that big a difference. The drug has a half life of about 10 hrs so a 5 fold difference is about 1 day. 10 days is a LOT of time to get rid of the drug. 20 half lives or 2 to the 20th power.
so, lying about the drug use is a big deal. If not lying, then the confirmatory test is one's friend.
Then it gets... interesting.
Detailed Answer:
Anywhere that does one urine test does many many of them. We don't do the more expensive confirmatory test if the screen is negative. So.... the nature of the question implies the initial test is positive. Mostly this is because someone lied about their use of drugs. In which case the confirmatory test is guaranteed to confirm the use of drugs. This could occur with a false positive in this case. the difference between the 100 and 500 cut off actually isn't all that big a difference. The drug has a half life of about 10 hrs so a 5 fold difference is about 1 day. 10 days is a LOT of time to get rid of the drug. 20 half lives or 2 to the 20th power.
so, lying about the drug use is a big deal. If not lying, then the confirmatory test is one's friend.
Above answer was peer-reviewed by :
Dr. Prasad
Thank you! The 500 ng/ml is the immunoassay screen. Normally, the sample wouldn't be tested further. However, if it did, should they not even worry about the 100 ng/ml confirmatory test?
Thank you! The 500 ng/ml is the immunoassay screen. Normally, the sample wouldn't be tested further. However, if it did, should they not even worry about the 100 ng/ml confirmatory test?
It probably won't get tested further. It was just a preemptive question out of concern. The test was only taken today and the results probably won't come back for at least a week. Also, how would alcohol affect the process?
It probably won't get tested further. It was just a preemptive question out of concern. The test was only taken today and the results probably won't come back for at least a week. Also, how would alcohol affect the process?
Brief Answer:
alcohol is irrelevant.
Detailed Answer:
It isn't going to have anything to do with the test. It doesn't cross react. It doesn't change the pharmacology much. it doesn't interact with any of the tests.
alcohol is irrelevant.
Detailed Answer:
It isn't going to have anything to do with the test. It doesn't cross react. It doesn't change the pharmacology much. it doesn't interact with any of the tests.
Above answer was peer-reviewed by :
Dr. Prasad
Brief Answer:
alcohol is irrelevant.
Detailed Answer:
It isn't going to have anything to do with the test. It doesn't cross react. It doesn't change the pharmacology much. it doesn't interact with any of the tests.
alcohol is irrelevant.
Detailed Answer:
It isn't going to have anything to do with the test. It doesn't cross react. It doesn't change the pharmacology much. it doesn't interact with any of the tests.
Above answer was peer-reviewed by :
Dr. Prasad
Lastly, a home drug test with a cutoff level of 1000 ng/ml was passed on Friday afternoon before the employment test on Monday. So its even more certain to pass?
Lastly, a home drug test with a cutoff level of 1000 ng/ml was passed on Friday afternoon before the employment test on Monday. So its even more certain to pass?
Brief Answer:
yes and probably.
Detailed Answer:
so, if it were 1000 with a half life of even 24 hrs... it would be 500 on sat. 250 on sun 125 on monday.
and
it was lower than 1000; probably lower than 100
it drops faster than that... probably about double, so it would be 500, 250, 125, then 63, 32, 16. Nobody goes down below 50.
so, wow, it's covered about 3 different ways (it passed the over the counter test; the time is long, the half life is short)
but,
it doesn't help if he uses again on Sunday.
that happens pretty frequently.
yes and probably.
Detailed Answer:
so, if it were 1000 with a half life of even 24 hrs... it would be 500 on sat. 250 on sun 125 on monday.
and
it was lower than 1000; probably lower than 100
it drops faster than that... probably about double, so it would be 500, 250, 125, then 63, 32, 16. Nobody goes down below 50.
so, wow, it's covered about 3 different ways (it passed the over the counter test; the time is long, the half life is short)
but,
it doesn't help if he uses again on Sunday.
that happens pretty frequently.
Above answer was peer-reviewed by :
Dr. Arnab Banerjee
Brief Answer:
yes and probably.
Detailed Answer:
so, if it were 1000 with a half life of even 24 hrs... it would be 500 on sat. 250 on sun 125 on monday.
and
it was lower than 1000; probably lower than 100
it drops faster than that... probably about double, so it would be 500, 250, 125, then 63, 32, 16. Nobody goes down below 50.
so, wow, it's covered about 3 different ways (it passed the over the counter test; the time is long, the half life is short)
but,
it doesn't help if he uses again on Sunday.
that happens pretty frequently.
yes and probably.
Detailed Answer:
so, if it were 1000 with a half life of even 24 hrs... it would be 500 on sat. 250 on sun 125 on monday.
and
it was lower than 1000; probably lower than 100
it drops faster than that... probably about double, so it would be 500, 250, 125, then 63, 32, 16. Nobody goes down below 50.
so, wow, it's covered about 3 different ways (it passed the over the counter test; the time is long, the half life is short)
but,
it doesn't help if he uses again on Sunday.
that happens pretty frequently.
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Above answer was peer-reviewed by :
Dr. Arnab Banerjee
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