Test Code BTBAS Butabarbital, Serum
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube: Red top (serum gel/SST are not acceptable)
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL
Collection Instructions:
1. Draw blood immediately before the next scheduled dose.
2. Within 2 hours of collection, centrifuge and aliquot serum into a plastic vial.
Useful For
Monitoring of butabarbital therapy
Method Name
Gas Chromatography Mass Spectrometry (GC-MS)
Reporting Name
Butabarbital, SSpecimen Type
Serum RedSpecimen Minimum Volume
0.6 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Serum Red | Refrigerated (preferred) | 28 days |
Ambient | 28 days | |
Frozen | 28 days |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Clinical Information
Butabarbital is a short to intermediate acting barbiturate derivative that is US Food and Drug Administration-approved for use in insomnia, in preoperative sedation, and as a hypnotic agent. Butabarbital is extensively metabolized and eliminated primarily by renal excretion. The elimination half-life ranges from 34 to 100 hours.
Reference Values
Therapeutic range:
2.0-3.0 mcg/mL Hypnosis
25 mcg/mL Sedation/Sleep
>30 mcg/mL Coma
Toxic concentration: >50 mcg/mL
Cutoff concentrations by gas chromatography mass spectrometry:
Butabarbital: 0.5 ng/mL
Interpretation
Butabarbital concentrations between 2.0 and 3.0 mcg/mL have been used for hypnosis/sedation with concentrations up to 25 mcg/mL used for sleep. Toxic concentrations have been reported as greater than 50 mcg/mL.
Cautions
The concentration at which toxicity occurs varies, and results should be interpreted in light of the clinical situation.
Specimens collected in serum gel tubes are not acceptable because the drug can absorb on the gel and lead to falsely decreased concentrations.
Day(s) Performed
Thursday
Report Available
3 to 9 daysPerforming Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80299
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
BTBAS | Butabarbital, S | 16236-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
622885 | Butabarbital, S | 16236-2 |