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22769 Phenobarbital

Phenobarbital
Test Code: PHENO
Synonyms/Keywords
Phenobarb​
Useful For
Phenobarbital (5-ethyl-5phenylbarbituric acid) is the most effective barbiturate in the long-term treatment of seizure disorders.  It is indicated for control in most types of seizures.  ​
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)
No​ Serum/ Plasma​Serum Separator Tube (SST)
Lithium-heparin Plasma Separator (PST),
Red Top Tube (RTT)
0.5 mL​0.2 mL​Collect 0.4 mL whole blood (red microtainer)​
Collection Processing Instructions
Serum or plasma separator tubes must have serum or plasma removed from gel within 1 hour of collection.​
Specimen Stability Information
Specimen Type Temperature Time
Serum/ Plasma​ ​ ​ Ambient​ 24 hours​
Refrigerate​ 7 days​
Frozen​ 1 year​
Rejection Criteria
Specimens remaining in gel separator​ tubes longer than 1 hour.
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Weston​
 ​Monday through Sunday​ ​Less than 2 hours​ ​Turbidimetric Inhibition Immunoassay Method/Siemens Dimension
Marshfield​ Monday through Sunday​ Less than 2 hours​ Emit* 2000 Rate Assay/Beckman AU​
Reference Range Information
Performing Location Reference Range
All Performing Sites 15-40 ug/mL
See Critical Value List for list of current critical values​
Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comments
80184 ​ ​ ​ ​ ​
Synonyms/Keywords
Phenobarb​
Ordering Applications
Ordering Application Description
​Centricity ​Phenobarbital
​Cerner ​Phenobarbital Level
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)
No​ Serum/ Plasma​Serum Separator Tube (SST)
Lithium-heparin Plasma Separator (PST),
Red Top Tube (RTT)
0.5 mL​0.2 mL​Collect 0.4 mL whole blood (red microtainer)​
Collection Processing
Serum or plasma separator tubes must have serum or plasma removed from gel within 1 hour of collection.​
Specimen Stability Information
Specimen Type Temperature Time
Serum/ Plasma​ ​ ​ Ambient​ 24 hours​
Refrigerate​ 7 days​
Frozen​ 1 year​
Rejection Criteria
Specimens remaining in gel separator​ tubes longer than 1 hour.
Useful For
Phenobarbital (5-ethyl-5phenylbarbituric acid) is the most effective barbiturate in the long-term treatment of seizure disorders.  It is indicated for control in most types of seizures.  ​
Reference Range Information
Performing Location Reference Range
All Performing Sites 15-40 ug/mL
See Critical Value List for list of current critical values​
For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Weston​
 ​Monday through Sunday​ ​Less than 2 hours​ ​Turbidimetric Inhibition Immunoassay Method/Siemens Dimension
Marshfield​ Monday through Sunday​ Less than 2 hours​ Emit* 2000 Rate Assay/Beckman AU​
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comments
80184 ​ ​ ​ ​ ​
For most current information refer to the Marshfield Laboratory online reference manual.