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Test Code
TOPIR
Test Name
Topiramate, Serum
CPT Codes
80201
Expected Turnaround Time
3 - 5 days
Clinical Utility
  • Identification and quantitation of topiramate.
  • Topiramate is an anti-epileptic used as an adjunctive treatment of partial-onset epilepsy and Lennox-Gastaut syndrome in children.
  • Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.
Specimen and Container Info

Preferred Specimen Type: Serum 

Preferred Collection Container: Red Top, Plain 

Desired Specimen Volume: 1 mL

  
Collection Instructions
  • Peak: Draw 2-4 hours after dose
  • Trough: Draw immediately prior to next dose
Processing and Submission Instructions
  1. Allow specimen to sit upright 30 minutes.
  2. Centrifuge for 5 minutes at 3000 rpm within 2 hours of collection.
  3. Transfer serum to plastic vial and refrigerate.
Transport Instructions

Transport to the laboratory refrigerated.  
Stability Requirements

Room Temperature

48 hours

Refrigerated

14 days

Frozen

30 days

Causes for Rejection

Specimens collected in separator tubes will be rejected.  
Methodology
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reference Intervals

 Analyte

Drug Dosage (mg)

Trough Level (µg/mL)

Peak Level (µg/mL)

Topiramate

100

4.5 - 6.6

6.5 - 9.2

Topiramate

200

8.0 - 12.0

12.0 - 16.0

Topiramate

400

14.0 - 20.0

20.0 - 30.0
Performing Location
Roble Road Core Laboratory
Alternate Names
Topamax
Testing Schedule
Routine, 3 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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