Pathology/Lab Coding Alert

Question: Our lab performs a quantitative and qualitative analysis of free and total carbamazepine for an epileptic patient. Does the "total" test include the measurement for "free" carbamazepine for coding purposes?

Michigan Subscriber

The test for total carbamazepine does not include the measure of free carbamazepine.

Code each test: If the lab performs both tests, you should report the work as follows:

80156 -- Carbamazepine; total

80157 -- ... free.

Physicians often prescribe carbamazepine for patients with epilepsy to control seizures. Especially while establishing effective dosage, physicians may order free and total carbamazepine blood tests. Because the lab performs two distinct tests, you can separately code each. Medicare's Correct Coding Initiative edits do not bundle these two codes.