Update Type: Test Down or Delayed
Test Updated: 12/20/2023
Test Overview
Test Methodology

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).

Test Usage

Therapeutic Drug Monitoring

Reference Range *

Clonazepam Anticonvulsant: 20 – 70 ng/mL; Anxiolytic: 4 – 80 ng/mL. Some individuals may show therapeutic response outside of these ranges, or may display toxicity within the therapeutic range, thus interpretation should include clinical evaluation. Note: Therapeutic ranges are for specimens drawn at trough (ie, immediately before next scheduled dose). Levels may be elevated in non-trough specimens.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Monday, Wednesday
Analytic Time

4 - 8 days

Soft Order Code
CZPS
MiChart Code
Clonazepam and 7-Aminoclonazepam, Sendout
Synonyms
  • Rivotral
  • Klonopin
  • Clonopin
  • CLONAZ
  • Clonazepam, Serum
Laboratory
Sendout
Reference Laboratory
Mayo CZPS
Section
Special Testing
Specimen Requirements
Collection Instructions

Collect specimen in a red top tube; do not use SST tube. Centrifuge within 2 hours, aliquot serum into a plastic vial and refrigerate.

Special Handling

Specimen must be spun and aliquotted within 2 hours of collection

Normal Volume
1.2 mL serum
Minimum Volume
0.6 mL serum
Rejection Criteria
SST tube not acceptable.
Additional Information

Test performed by Mayo Clinic Laboratories.

Billing
CPT Code
80346
Fee Code
20036
LOINC
3494-2