CPT® Code 80159

CPT® Code 80159 refers to a laboratory test specifically designed to measure the levels of clozapine in the blood. Clozapine, marketed under various brand names such as Clozaril, FazaClo, Froidir, and Leponex, is classified as an atypical antipsychotic medication. It is primarily utilized in the treatment of schizophrenia, particularly in patients who have not responded to or cannot tolerate other antipsychotic medications. Monitoring clozapine levels is crucial for ensuring therapeutic efficacy and minimizing potential toxicity. The test is performed through a blood draw, specifically a pre-dose or trough sample, which is essential for accurate measurement of the drug's concentration in the bloodstream. The analysis of the blood sample is conducted using advanced techniques such as quantitative liquid chromatography-tandem mass spectrometry, which allows for precise quantification of clozapine levels in serum or plasma. This testing is vital for clinicians to make informed decisions regarding dosage adjustments and to ensure patient safety during treatment.