Sign in →

Test Code CARBAM Carbamazepine Level, Total, LAB21


Particle Enhanced Turbidimetric Inhibition Immunoassay

Performing Laboratory

St. Luke's Hospital Cedar Rapids

Specimen Requirements


Preferred: Green-top (lithium heparin) tube

Acceptable: Gold-top serum gel tube, plain red-top tube, or lavender-top (EDTA) tube

Specimen Volume: 0.1 mL of plasma or serum

Stability: Serum or plasma should be physically separated from cells as soon as possible

                 with a maximum limit of two hours from the time of collection.

Collection Instructions: Trough level should be drawn immediately prior to next dose.

                 Time to peak level is 4 to 8 hours after conventional formulations, or more than

                  12 hours after a single dose with sustained release formulations.

Note: 1. Time to steady state for carbamazepine is after 2 to 6 days of chronic oral dosing.

          2. Levels may be ordered at any time toxicity is suspected.

          3. Label specimen appropriately (plasma).

Reference Values

Therapeutic range: 4.0-12.0 mcg/mL

Critical value: ≥15.0 mcg/mL

Day(s) Test Set Up

Monday through Sunday

Test Classification and CPT Coding


Useful For

Carbamazepine is used in the treatment of both psychomotor and grand mal seizures as well as trigeminal neuralgia. Carbamazepine therapy is monitored for suspected inadequate dose or toxicity.