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Benzodiazepines Screen, Urine

Item Value
Test Update Information Effective 01/14/2013, the platform used for the benzodiazepine immunoassay screen has changed from the Abbot Axsym to the Beckman UniCel DxC 800.
Approval req'd? No
Available Stat? Yes
Test code BENZ
Test group Benzodiazepine
Performed by Parnassus Chemistry
In House Availability Test available 24 hours per day 7 days per week
Method β-glucuronidase treatment followed by competitive enzyme immunoassay method (Beckman UniCel DxC800 analyzer)
Container type Urine cup
Amount to Collect See preferred volume
Sample type Random urine
Preferred volume 1 mL urine
Min. Volume 0.5 mL urine
Normal range Negative

Note: a negative result indicates that this class of drugs is not present, or they are present at a concentration below the cutoff concentration of 200 µg/L
Stability Refrigerated 1 week, frozen at -20C 2 weeks
Turn around times Stat 2 hours, routine 4 hours
Additional information A level < 200 µg/L is considered negative by this test. A positive result is ≥ 200 µg/L and indicates the presence of this class of drugs. This immunoassay is only a screening test and is not definitive. Results cannot be used for medico-legal purposes.

This assay detects a number of benzodiazepines at varying concentrations.

Click here for List of Cross Reactive Substances

False positive results may occur due to other cross reacting substances, however, positive results are NOT routinely confirmed by a second method. If confirmation of the test result is required, it is the responsibility of the physician to separately order a specific confirmatory test for the drug identified. Samples are held for 7 days. Contact laboratory at x 31667 to request confirmatory testing.

Benzodiazepines can be detected from 6 hours up to 14 days after a single use (Negrusz A et al, Elimination of 7-aminoclonazepam in urine after a single dose of clonazepam. Anal Bioanal Chem, 2003, 376:123-130) and for longer in chronic users (French D et al, Choosing the right benzodiazepine assay: impact on clinical decision making. Lab Medicine, 2010, 41(4):2-6)
LOINC code 14316-4
Last Updated 3/24/2013 7:38:24 PM
Entry Number 111
Lab Procedure Link Click here for Procedure
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