Days Set Up
Daily, 24 hrs.
Analytic Time
2 hours
MiChart Code
Phenytoin Level, Free
Soft Order Code
FDIL
Test Updated:
Synonyms
Dilantin, Protein Free
Free Dilantin
Free Phenytoin
FDIL
FREE DILANTIN LEVEL
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Test Overview
Test Methodology
Kinetic Immunoassay (KIMS).
Test Usage
Evaluate phenytoin toxicity
Reference Range
1-2 mcg/mL (Approximately 10% of the total drug concentration). Toxic levels: greater than 3 mcg/mL.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Billing Information
CPT Code
80186
Pro Fee Code
LOINC
3969-3