Biomarkers · Chemical
Phenytoin
- Also listed as
- Phenytoin (Dilantin), Serum
- Primary unit
- ug/mL
- LOINC codes
- 3968-5
- Tests that measure Phenytoin
- Labcorp 2, Quest Diagnostics 1
Tests
Check the catalog code, specimen, method and preparation for every test that measures Phenytoin. Select up to five tests to compare them side by side.
Labcorp 2 tests
Single-analyte tests
Phenytoin, Serum or Plasma 007401
Serum · Fasting not stated · Turnaround Within 1 day
Labcorp catalog pageMethod and collection
- Method
- Immunoassay
- Collection
- Transfer separated serum or plasma to a plastic transport tube. IV: two to four hours after loading dose. Oral: peak: three to nine hours after dose, immediately prior to next dose. Optimal resampling after change in dosage: 48 hours.
- Reference notes
- Therapeutic: • <90 days: 6.0−14.0 μg/mL • Adults: 10.0−20.0 μg/mL
Panels that include this biomarker
Phenytoin, Free and Total, Serum 070706
2 analytes · Serum · Fasting not stated · Turnaround 2 - 5 days
Labcorp catalog pageMethod and collection
- Method
- Total: immunoassay; Free: ultrafiltrate assayed by immunoassay
- Collection
- Transfer separated serum or plasma to a plastic transport tube. Collect specimen just prior to next dose. Serum or plasma must be separated from cells within 45 minutes of collection. Send serum or plasma in a plastic transport tube.
Quest Diagnostics 1 test
Single-analyte tests
Phenytoin 713
Serum · Fasting not stated · Turnaround Set up: Tues-Sat (All shifts); Report available: 4 days
Quest Diagnostics catalog pageMethod and collection
- Method
- Immunoassay (IA)
- Preparation
- Collect as a trough just prior to next dose. For patients receiving fosphenytoin therapy, collect as a trough at least 2 hours after IV infusion or at least 4 hours after IM injection.
- Reference notes
- 10.0-20.0 mg/L
0 of 5 tests selected
Pick one moreSources
2 tests: codes, specimens, methods, preparation and reference intervals.
Quest Diagnostics test catalog
1 test: codes, specimens, methods, preparation and reference intervals.
LOINC 3968-5
Regenstrief Institute codes that identify the same result across labs.
Search ClinicalTrials.gov for Phenytoin
Registered studies that measure Phenytoin, on the U.S. National Library of Medicine registry.
Verify these ranges and sources
We compile this page from named laboratory catalogs, guidelines and studies. Labs calculate reference intervals from the people they test, for one assay method and one population group, so an interval describes that population rather than an optimal target.
Interpret your own results with a licensed clinician, or track your lab history and health goals in Aumnivida.
Spotted an error? Email hello@biomarkerlens.com with the page URL and the primary source that corrects the entry.