Phenytoin

Test Name

Phenytoin

Alternate Description

Dilantin

LIS Code

PHNY

Availability

24 hours a day, seven days a week

Lab Section

Chemistry

Fluid Type

Whole blood plasma 

Specimen Tube Type Transport

Gel Green Top

Container Whole Blood Required

4 ml whole blood in a Gel Green Top

Critical Value

>25 ug/mL

Summary Test Name

Phenytoin

Specimen Preparation Outreach

Spin right away, separate plasma into plastic 12 x 75 pour-off tube. Cap with plastic stopper. Refrigerate until courier pickup.

Specimen Stability

4 days refrigerated, if spun and plasma removed from gel; 6 hours on the gel

Minimum Volume

1 full green microtainer or 1 mL in a pediatric green top tube.

Specimen Transport

Refrigerate

Specimen Preparation In House

Spin and refrigerate until analysis

Stat Availability

24 hours a day, seven days a week

Test Turnaround Time Routines And Stats

R 4 hours S 1 hour

Reference Value

Therapeutic range: 10-20 ug/mL

Additional Test Information

TROUGH: Trough levels should be drawn immediately before administering the next dose. PEAK: Collect 2 hours after IV push or 8 hours after oral dose.