Secobarbital, Serum
Use
Secobarbital is a short-acting barbiturate with hypnotic properties used as a preanesthetic agent and in the short-term treatment of insomnia. The test is useful for monitoring secobarbital therapy to ensure therapeutic levels while avoiding toxicity. Secobarbital is administered orally, and its hypnotic effect lasts about 3 to 4 hours. Monitoring concentrations above 5 mcg/mL is critical as they may be associated with toxicity. The drug has a volume of distribution of 1.6 to 1.9 L/kg and is 46% to 70% bound to plasma proteins, with metabolism primarily occurring via hepatic microsomal enzymes.
Special Instructions
Specimens should be collected immediately before the next scheduled dose. Within 2 hours of collection, serum must be centrifuged and aliquoted into a plastic vial. If not ordering electronically, complete one of the required test request forms and send it with the specimen. Ensure serum is not collected in serum gel tubes as they lead to drug absorption and falsely decreased concentrations.
Limitations
The concentration at which secobarbital toxicity occurs can vary among individuals, and test results should be interpreted in light of the clinical situation. The test's usage of serum gel tubes is not recommended due to potential absorption issues that may result in falsely decreased drug concentrations. Potential interfering substances should be considered when interpreting results.
New York Approved
Methodology
Mass Spectrometry (GC-MS)
Biomarkers
LOINC Codes
- 4028-7
- 4028-7
Result Turnaround Time
3-9 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1.5 mL
Minimum Volume
0.6 mL
Container
Plastic vial
Collection Instructions
Collect specimen immediately before the next scheduled dose. Within 2 hours of collection, centrifuge and aliquot serum into a plastic vial.
Causes for Rejection
Serum gel tubes are not acceptable. Gross hemolysis, gross lipemia, and gross icterus are acceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 28 days |
| Refrigerated | 28 days |
| Frozen | 28 days |