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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.
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The clozapine level measurement is indicated for patients undergoing treatment with clozapine who require monitoring to ensure therapeutic effectiveness and safety. The following conditions warrant the performance of this test:
The procedure for measuring clozapine levels involves several critical steps to ensure accurate results. First, a healthcare professional will perform a venipuncture to obtain a blood sample from the patient. This blood draw is typically conducted as a pre-dose or trough sample, meaning it is taken just before the next scheduled dose of clozapine. This timing is essential for accurately assessing the drug's concentration in the bloodstream. Once the blood sample is collected, it is sent to a laboratory for analysis. In the lab, the serum or plasma is subjected to quantitative liquid chromatography-tandem mass spectrometry, a sophisticated analytical technique that allows for precise measurement of clozapine levels. This method is preferred due to its high sensitivity and specificity, ensuring that even low concentrations of the drug can be accurately detected and quantified. The results of this test will guide clinicians in making informed decisions regarding the patient's clozapine dosage and overall treatment plan.
After the blood sample has been collected for clozapine level testing, there are no specific post-procedure care requirements for the patient. However, it is essential for healthcare providers to communicate the importance of adhering to the prescribed clozapine regimen and to schedule follow-up appointments for ongoing monitoring. Patients should be informed about the significance of regular blood tests to ensure that clozapine levels remain within the therapeutic range, which is crucial for effective treatment and minimizing the risk of adverse effects. Additionally, any abnormal results should be promptly addressed by the healthcare provider to adjust the treatment plan as necessary.
| Short Descr | DRUG ASSAY CLOZAPINE | Medium Descr | DRUG ASSAY CLOZAPINE | Long Descr | Clozapine | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 2 |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | GZ | Item or service expected to be denied as not reasonable and necessary | 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | 91 | Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. | AR | Physician provider services in a physician scarcity area | GA | Waiver of liability statement issued as required by payer policy, individual case | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | Q4 | Service for ordering/referring physician qualifies as a service exemption | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician |
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| 2014-01-01 | Added | Added |
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