Back

Phenytoin, Total

Alternative Names/Synonyms	Dilantin, Diphenylhydantoin
Laboratory	Core Laboratory & Transfusion Medicine
Sub-section	Biochemistry
Specimen Type	Blood
Test Code	PHEN, PHEPL

Clinical Significance

Monitoring therapy, determining compliance and assessing toxicity.

Specimen Requirements (Sample Type)

Serum, Plasma

Specimen Requirements (Volume (mL))

0.5 mL

Specimen Requirements (Tube Type)

Serum (Gold SST)
Plasma (Light Green PST)
Collection Containers – Tube Types

Collection Requirements

Blood Collection Instructions

Sample Stability

Room Temperature: 4 days

Fridge: 4 days @ 2-8°C

Freezer: 1 month @ -20°C

Cause for Rejection

Specimen Acceptability and Transport Guidance

Instrument, Methodology

Roche cobas c 502, immunoturbidimetric

Test Availability

24 hours a day, 7 days a week

STAT Turnaround Time

1 hour

Routine Turnaround Time

3 hours

Reference Ranges

40 - 80 µmol/L

In case of discrepancies, always interpret results using reference ranges as stated on laboratory reports and/or electronic patient chart.

Laboratory Contact Information

416-586-4800 extension 4688