Sign in →

Test Code BUTAS Butalbital, Serum

Reporting Name

Butalbital, S

Useful For

Monitoring butalbital therapy

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Serum Red


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 next scheduled dose.

2. Centrifuge and aliquot serum into a plastic vial within 2 hours of collection.


Specimen Minimum Volume

0.6 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Red Refrigerated (preferred) 14 days
  Ambient  14 days
  Frozen  14 days

Reference Values

Therapeutic concentration: <10 mcg/mL

Toxic concentration: ≥10 mcg/mL

Day(s) Performed

Thursday

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
BUTAS Butalbital, S 6895-7

 

Result ID Test Result Name Result LOINC Value
8427 Butalbital, S 6895-7

Clinical Information

Butalbital, a short-acting barbiturate with hypnotic properties, is used in combination with other drugs such as acetaminophen, salicylate, caffeine, and codeine.(1)

 

Butalbital is administered orally. The duration of its hypnotic effect is about 3 to 4 hours. The drug distributes throughout the body, with a volume of distribution of 0.8 L/kg, and about 26% of a dose is bound to plasma proteins. The half-life of butalbital is about 35 to 88 hours. Excretion occurs mainly in the urine.(1,2)

Interpretation

Butalbital concentrations of 10 mcg/mL or greater have been associated with toxicity.

Cautions

Specimens collected in serum gel tubes are not acceptable because the drug can absorb on the gel and lead to falsely decreased concentrations.

Clinical Reference

1. Langman LJ, Bechtel LK, Holstege CP. Clinical toxicology. In: Rifai N, Chiu RWK, Young I, Burnham C-AD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:454-454.e484

2. Baselt RC. Disposition of Toxic Drugs and Chemical in Man. 12th ed. Biomedical Publications; 2020

3. Milone MC, Shaw LM. Therapeutic drugs and their management. In: Rifai N, Chiu RWK, Young I, Burnham C-AD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:420-453

4. Mihic SJ, Mayfield J. Hypnotics and sedatives. In: Brunton LL, Knollmann BC, eds. Goodman and Gilman's The Pharmacological Basis of Therapeutics. 14th ed. McGraw-Hill Education; 2023

Method Description

Barbiturates are extracted from serum using solid-phase extraction techniques. The serum is buffered and eluted with organic solvent. The organic phase is dried, reconstituted, and analysis performed by gas chromatography-mass spectrometry using selected ion monitoring. The assay utilizes deuterated barbiturates as internal standards.(Unpublished Mayo method)

Report Available

3 to 9 days

Specimen Retention Time

2 weeks

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Method Name

Gas Chromatography-Mass Spectrometry (GC-MS)

Forms

If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.

Secondary ID

8427