When a GC-MS (gas chromatography-mass spectrometry) is done for
Clonazepam and Diazepam, what is the exact % of accurracy that
Clonazepam not be mistaken for Diazepam, since thay are so close in
structure.  Is it possible that a person taking only Clonazepam take a
urine test for toxiclogy and the GC-MS test show up as Diazepam and
Clonazepam in the urine?  I am a RN and have a patient only on
Clonazepam and the urine test done showed a high level of
Benzodiazepines.  A GS-MS test was then ordered to determine what
Benzodiazepines were present.  The result showed the Clonazepam and
Diazepam as metabolites.  The patient has not taken Diazepam.  This
patient is closely mointered and has to check in daily for random
urines.  This patient has been on Clonazepam for several months which
in urines have only indicated positive for Benzodiazepines no GC-MS
tests were run on these until recently.  This patient had gotten a
presciption filled for Clonazepam at a different pharmacy then he/she
has before for this med.  This prescription is a different brand of
Clonazepam from the one he/she has been taking.  If 2 different brand
names of Clonazepam were taken together, could one brand show up as
Clonazepam and the other Diazepam or would every brand definately
without a doubt show up in a GC-MS test as just clonazepam?  These 2
benzodiazepines are so similiar in chemical structure, could the have
any chance of being mistaken one for the other?  The other meds this
patient is on (Suboxone,Adderall,and Ambien).  Could any of these meds
when broken down by chemical structure
(Clonazepam,Suboxone,Adderall,Ambien) resemble Diazepam?  Which would
cause a GC-MS urine test to indicate a false positive of Diazepam?  Is
every GC-MS test 100% accurate or is there % of possible false
readings?

The structures of Diazepam ans clonazepam are quite similar, but a
GC-MS could easily differentiate the two.  HOWEVER, the technician may
not be looking at the actual structure, but instead be looking at
metabolites.   The metabolites of the two drugs may be very similar,
or even identical.   The test is probably giving a positive for a
diazepam, not necessarily exactly diazepam.  So in short, yes, it is
concievable that there is a type of false positive, without actually
being a false positive.  Clonazepam is a Benzodiazepine.

The differnt brands the FDA assures us are chemically equivalant in
their active ingredients, so a different brand should not change
anything.