www.chiefsplanet.com is where I head to get all of my medical questions answered! (Seriously though I know we have some people here knowledgeable about this stuff)
Went in to do my yearly drug screening due to me taking a benzodiazepine on a regular basis about a week ago. Got the results a day later along with a call from my doctor saying that my test came back negative for benzos. They asked me if I had been taking the medication as prescribed, which I have. They said no big deal, we'll just redo the test.
Did the sample again yesterday, and again it was negative. The doctors office isn't open today so I'm not sure what the deal is.
Anyone know why I'd be coming up negative on the screening? Klonipon is the drug, if that helps any. [Reply]
There are a lot of variables in a drug test. He can still have it in his system and not have enough of the metabolite to spike a positive test. This can be exacerbated by other drugs or supplements one takes. Clonazepam is a CYP3A4 substrate, of which there are many inducers (phenobarb, carbamazepine, oxcarbazapine, rifampin, phenytoin, smoking). Inducers can cause a person to clear the drug much faster than they would under normal physiological conditions.
Have your pills recently changed color or shape? It's possible the pharmacy gave you the wrong medication--for example Clonidine instead of Clonazepam. If not, the pharmacy would be able to tell you the lot number of the mediation and the supplier. Should others have similar issues, they would need to institute a recall due to adulteration, as clonazepam is primarily used for seizure control, and prompt withdrawal will cause exacerbations and potentially status epilepticus. [Reply]
Originally Posted by 'Hamas' Jenkins:
There are a lot of variables in a drug test. He can still have it in his system and not have enough of the metabolite to spike a positive test. This can be exacerbated by other drugs or supplements one takes. Clonazepam is a CYP3A4 substrate, of which there are many inducers (grapefruit, protease inhibitors, cimetidine, cyclosporine, macrolides, amiodarone, azole antifungals, non-DHP calcium channel blockers). Inducers can cause a person to clear the drug much faster than they would under normal physiological conditions.
Have your pills recently changed color or shape? It's possible the pharmacy gave you the wrong medication--for example Clonidine instead of Clonazepam. If not, the pharmacy would be able to tell you the lot number of the mediation and the supplier. Should others have similar issues, they would need to institute a recall due to adulteration, as clonazepam is primarily used for seizure control, and prompt withdrawal will cause exacerbations and potentially status epilepticus.
Oh, you beat me to it. I was going to post the same thing. [Reply]
Originally Posted by 'Hamas' Jenkins:
There are a lot of variables in a drug test. He can still have it in his system and not have enough of the metabolite to spike a positive test. This can be exacerbated by other drugs or supplements one takes. Clonazepam is a CYP3A4 substrate, of which there are many inducers (phenobarb, carbamazepine, oxcarbazapine, rifampin, phenytoin, smoking). Inducers can cause a person to clear the drug much faster than they would under normal physiological conditions.
Have your pills recently changed color or shape? It's possible the pharmacy gave you the wrong medication--for example Clonidine instead of Clonazepam. If not, the pharmacy would be able to tell you the lot number of the mediation and the supplier. Should others have similar issues, they would need to institute a recall due to adulteration, as clonazepam is primarily used for seizure control, and prompt withdrawal will cause exacerbations and potentially status epilepticus.
1.5mg daily. The pill hasn't changed recently, still the same shape and color.
I talked to one of the nurses at the doctors office this morning. She said the cutoff the lab uses for a negative/positive test may be set too high. She's going to order a test that has a lower cutoff and see what kind of results we get. [Reply]
Originally Posted by htismaqe:
1.5mg isn't a low dose.
No it's not. 0.5mg TID.
I don't think there's anything wrong with the medication itself. I'm fairly certain I'd know if it wasn't working. (Bad batch, etc) There's no recalls out that I can find anywhere. [Reply]
Immunoassay methodology isn't very reliable when it comes to UDS. They have can easily have false positives because they are picking up the structure of the molecule and if someone has taken something similar in structure then it may flag as positive. Im not sure why they don't pick up clonazepam, but I had read that they have false negatives ~30% of the time with benzos.
See if they can just call into Quest and have then do the mass spectrometry for Benzos and that should pick it up. [Reply]
Originally Posted by dlphg9:
Immunoassay methodology isn't very reliable when it comes to UDS. They have can easily have false positives because they are picking up the structure of the molecule and if someone has taken something similar in structure then it may flag as positive. Im not sure why they don't pick up clonazepam, but I had read that they have false negatives ~30% of the time with benzos.
See if they can just call into Quest and have then do the mass spectrometry for Benzos and that should pick it up.
Originally Posted by dlphg9:
Immunoassay methodology isn't very reliable when it comes to UDS. They have can easily have false positives because they are picking up the structure of the molecule and if someone has taken something similar in structure then it may flag as positive. Im not sure why they don't pick up clonazepam, but I had read that they have false negatives ~30% of the time with benzos.
See if they can just call into Quest and have then do the mass spectrometry for Benzos and that should pick it up.
Back to the same god damn problem as last year around this time. The nurse called me and had an attitude about me not taking my medication as prescribed. Told her the story of last year and about needing a more specialized test. According to them, that test is no longer available and I need to come back in and repeat the SAME test that is reliably giving me false results. I tell them I don't want to keep paying for labs that I know are going to come back as negative.