Diazepam and Metabolites, Serum
Use
Diazepam is an anxiolytic agent used to reduce neuronal depolarization, which results in decreased action potentials. It enhances the action of GABA by binding to A-type GABA receptors, which facilitates chloride ion entry. It is utilized as a muscle relaxant, procedural sedation agent, and sedative-hypnotic to treat withdrawal states, and other conditions such as seizures. Monitoring serum levels of diazepam and its metabolites is crucial for assessing compliance and ensuring appropriate therapeutic levels, particularly to prevent toxicity. High concentrations of diazepam and nordiazepam can indicate toxicity, especially when levels exceed 3000 ng/mL.
Special Instructions
When not ordering electronically, fill out the Therapeutics Test Request form (T831) and send it with the specimen. Ensure that the specimen collected is a red-top tube and avoid using serum gel/SST tubes.
Limitations
This test measures both diazepam and its metabolite nordiazepam to ensure accurate therapeutic monitoring. It is essential for assessing both compliance and potential toxicity in treated individuals. Since diazepam is metabolized in the liver to various metabolites, the clearance can be notably reduced in older individuals and those with hepatic impairment. Serological monitoring is less informative for seizure control due to direct observation of therapeutic effectiveness clinically.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 49044-1
- 3548-5
- 3537-8
- 16757-7
- 3886-9
- 10343-2
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.3 mL
Container
Plastic vial; Collection Container/Tube: Red top (Serum gel/SST not acceptable)
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 28 days |
| Refrigerated | 28 days |
| Frozen | 28 days |