Phenytoin, Total
Total Phenytoin, Dilantin Level
Testing Information
Sample Type
Serum
Test Codes
630340
CPT Code
80185
Testing Area
Core Lab - Chemistry
Test Methodology
Abbott Alinity - Enzyme Immunoassay
Reference Range
0-3 years: 6.0-15.0 mcg/mL>4 years: 10-20 mcg/mLCritical Value: >30 mcg/mL
Expected Turnaround Time
Results Available 24 hours from Receipt
Specimen Collection Criteria
Collect one gold top SST tube (minimum whole blood: 1 mL). Let specimen clot for 30-60 minutes and then centrifuge to separate serum from cells. Refrigerate after centrifugation.
Rejection Criteria
Grossly hemolyzed specimens, quantity not sufficient, improperly labeled
Specimen Validity and Retention
Centrifuged SST Tubes:Room Temperature (20-25°C): 24 hoursRefrigerated (2-8°C): 7 daysFrozen (-20°C or greater): UnacceptableSerum Aliquots:Room Temperature (20-25°C): 24 hoursRefrigerated (2-8°C): 7 daysFrozen (-20°C or greater): 7 daysSpecimens retained for 7 days after testing
Courier Transportation
Transport centrifuged tube refrigerated (2-8°C)
Clinical Utility
Phenytoin is an anticonvulsant drug. This assay is used to monitor the therapeutic drug level and potential toxicity.
