Carbamazepine, Total / Carbamazepine, Free (Carbamazepine Free is not available without a Carbamazepine Total.)
1-4 days after setup at PeaceHealth Laboratories’ reference lab.
80156-90 / 80157-90
Specimen Collection Details
One 5 mL red top tube. Do not use serum separator tube (SST).
Allow to clot, centrifuge and immediately separate serum from cells into a plastic vial. Refrigerate.
5 days ambient, 5 days refrigerated, or 4 months frozen.
2 mL serum
1 mL serum
Free carbamazepine may be important to monitor in patients with altered or unpredictable protein binding capacity. Carbamazepine is also subject to drug-drug interactions due to displacement of protein binding and extensive metabolism. Cross-reactivity with metabolites may account for differences in carbamazepine among analytical methods. Calculating percent free attempts to minimize differences in assay cross-reactivity and may be useful in dose optimization.