Chlordiazepoxide and Metabolites

Test Code

91123

CPT Codes
80299

Includes

Chlordiazepoxide, Norchlordiazepoxide, Nordiazepam

Preferred Specimen

2 mL serum collected in a red top tube (no gel)

Patient Preparation
Collect at trough concentration, i.e., just before the administration of the next dose.

Minimum Volume

1 mL

Instructions

Serum separator tubes (SST) are not acceptable; use polypropylene tubes and ship on cold pack by overnight courier.

Transport Container

Polypropylene tubes

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 5 days
Frozen: 14 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Received room temperature • Serum separator tube (SST)

Methodology
Chromatography/Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Fri; Report available: 6-15 days

Reference Range

Chlordiazepoxide	100-3000 ng/mL
Norchlordiazepoxide	100-3000 ng/mL
Nordiazepam	100-1500 ng/mL

Clinical Significance

This definitive drug assay is used to measure concentrations of chlordiazepoxide, norchlordiazepoxide, and nordiazepam in serum. This therapeutic drug monitoring assay may be used to assess if chlordiazepoxide and metabolites are within therapeutic range. Urine and oral fluid are the specimens of choice for routine monitoring of patients taking prescription drugs.

Chlordiazepoxide is a long-acting benzodiazepine used to treat adults for anxiety disorder, preoperative apprehension and anxiety, and withdrawal symptoms of acute alcohol use disorder. It is also used to treat children older than 6 years for anxiety.

Chlordiazepoxide has several active metabolites, and prolonged duration of action may lead to serious adverse effects in older individuals, children, and individuals with disabilities or hepatic or renal impairment. Common adverse effects include drowsiness, fatigue, dizziness, ataxia, forgetfulness, slurred speech, irritability, and rash. Chlordiazepoxide intoxication and overdose can be life-threatening, especially when chlordiazepoxide is combined with alcohol and other central nervous system depressants [1,2]. However, routine quantitative tests of chlordiazepoxide are not needed unless medical conditions warrant monitoring or for individuals taking other drugs that increase the risk of intoxication [2].

The results of this test should be interpreted in the context of pertinent clinical history and physical examination findings.

References
1. Chlordiazepoxide. In: Fuller MA, et al, eds. Drug Information Handbook for Psychiatry. 7th ed. Lexi-Comp Inc; 2009:316-319.
2. Whyte IM. Benzodiazepines. In: Dart RC, et al. Medical Toxicology. 3rd ed. Lippincott Williams & Wilkins; 2004:811-823.

Performing Laboratory

Quest Diagnostics Nichols Institute-Valencia

8407 Fallbrook Ave, Suite 100

West Hills, CA 91304-3226

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.