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The CPT® Code 80156 refers to a laboratory test that measures the total level of carbamazepine in the blood. Carbamazepine, commonly known by its brand name Tegretol, is an anticonvulsant medication primarily used to manage epilepsy. Additionally, it serves as an analgesic for conditions such as trigeminal neuralgia. The measurement of total carbamazepine levels is crucial for determining the appropriate dosage for patients undergoing treatment for epilepsy and for monitoring potential toxicity associated with the drug. The test evaluates both the total amount of carbamazepine present in the bloodstream and its relationship with protein binding. Typically, about 75% of circulating carbamazepine is bound to proteins in the blood. However, in certain patients, carbamazepine can be displaced from these proteins, leading to elevated levels of free carbamazepine. This situation necessitates careful monitoring, as lower total levels may still result in toxicity due to increased free drug levels. The test is performed by obtaining a blood sample through venipuncture, and the serum is analyzed using various techniques, such as high-performance liquid chromatography or fluorescent polarization immunoassay, to ensure accurate measurement of the total carbamazepine concentration.
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The total carbamazepine test (CPT® Code 80156) is indicated for the following conditions:
The procedure for conducting the total carbamazepine test involves several key steps:
After the total carbamazepine test is performed, there are several considerations for post-procedure care. Patients may be advised to resume normal activities immediately following the blood draw, as there are typically no significant side effects associated with the venipuncture. However, it is important for healthcare providers to communicate the results of the test to the patient in a timely manner. If the results indicate elevated levels of carbamazepine, further evaluation and potential adjustments to the medication regimen may be necessary to ensure patient safety and effective treatment. Additionally, patients should be monitored for any signs of toxicity, especially if they are on carbamazepine therapy, to prevent adverse effects related to elevated free drug levels.
| Short Descr | ASSAY CARBAMAZEPINE TOTAL | Medium Descr | DRUG ASSAY CARBAMAZEPINE TOTAL | Long Descr | Carbamazepine; total | 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 | CCS Clinical Classification | 235 - Other Laboratory |
| 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. | GW | Service not related to the hospice patient's terminal condition | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | 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. | 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. | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter |
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| 2013-01-01 | Changed | Medium description changed per AMA 2013 corrections document dated January 25, 2013. |
| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Changed | Code description changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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