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Test Code
CZEX
Test Name
Carbamazepine Epoxide and Total
CPT Codes
80156, 80161
Included Tests
  • Carbamazepine-10, 11 Epoxide
  • Total Carbamazepine
Expected Turnaround Time
3 - 5 days
Clinical Utility

Therapeutic drug management.
Specimen and Container Info

Specimen Type: Serum

Alternate Specimen Type: Plasma

Collection Container: Red Top, Plain

Alternate Collection Container: Green Top (Lithium or Sodium Heparin)

Desired Specimen Volume: 2 mL
Collection Instructions
  1. Collect a red top, plain tube via venipuncture
Processing and Submission Instructions
  1. Separate serum from cells within 2 hours of collection.
  2. Transfer 2 mL of serum to a clear aliquot tube (screw cap).
Patient Preparation

 Trough levels are most reproducible.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

3 days

Refrigerated

14 days

Frozen

6 months
Causes for Rejection
  • Gel-barrier tubes
Methodology
Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS)
Reference Intervals

See patient report.

Alternate Names
  • Carbatrol®
  • Epitol®
  • Tegretol®
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Routine, 2 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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