Item Value
Test name Phenytoin, total
Available Stat? Yes
Turn around times STAT 1 hour, Routine 4 hours
In House Availability Test available 24 hours per day 7 days per week
Performed by Parnassus & Mission Bay Chemistry
Normal range
Therapeutic: 10-20 mg/L


Source: Phenytoin: Drug information, Copyright 1978-2012 Lexicomp, Inc. Accessed in UpToDate, August 2012

Therapeutic ranges adopted or modified from the literature based on recommendations of UCSF Pharmacists
Container type Red top
Amount to Collect 1 mL blood
Collection Instructions Time to steady state: 3-4 days

Collect samples 30 minutes before AM dose.

Draw at least 4 hours post-IV dose and 6-9 hours post-PO dose

Indicate time of draw on requisition.
Sample type Serum

If you have additional questions regarding this test, please call: 415-353-1667