Lorazepam
Also known as: LORAZ
Use
The Lorazepam test is used to optimize dosing and monitor patient adherence to the medication. It assists in ensuring that the drug is being administered at therapeutic levels while avoiding toxic levels. Lorazepam is often prescribed for the management of anxiety disorders, insomnia, and is used in hospital settings for sedation. Monitoring the drug levels is crucial to manage the effectiveness and safety of the treatment, as well as to adjust dosages accordingly.
Special Instructions
Collect the sample as a predose (trough) draw at steady state concentration for accurate therapeutic drug monitoring. Use appropriate collection tubes such as gray (potassium oxalate/sodium fluoride), plain red, green (sodium heparin), lavender (K2 or K3EDTA) or pink (K2EDTA). Avoid gel separator tubes and samples collected in light blue (sodium citrate) tubes.
Limitations
Limitations of the Lorazepam test include potential interference from hemolyzed samples and samples collected in gel separator or light blue (sodium citrate) tubes, which are not acceptable. The test measures lorazepam levels using liquid chromatography-tandem mass spectrometry, which is a precise and accurate method, but improper handling of specimens, such as extended delays before separation from cells or repeated freeze/thaw cycles, may affect results. Thus, specimens must be refrigerated with specific stability constraints: Ambient stability for 1 week, refrigerated for 2 weeks, and frozen stability for up to 3 years.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 3724-2
Result Turnaround Time
1-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
2 mL
Minimum Volume
1 mL
Container
ARUP standard transport tube
Collection Instructions
Separate serum or plasma from cells ASAP or within 2 hours of collection.
Patient Preparation
Timing of specimen collection: Predose (trough) draw at steady state concentration.
Causes for Rejection
Gel separator tubes. Plasma or whole blood collected in light blue (sodium citrate). Hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 2 weeks |
| Frozen | 3 years |
Other tests from different labs that may be relevant