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The CPT® Code 80188 refers to a laboratory test specifically designed to measure the levels of primidone in the blood. Primidone, which is commonly known by its brand name Mysoline, is classified as an anticonvulsant medication. It is primarily prescribed for the management of seizures and essential tremor, conditions that involve abnormal electrical activity in the brain. The mechanism of action of primidone involves the reduction of this electrical activity, thereby helping to stabilize neuronal function and prevent seizure episodes. The administration of primidone is typically done orally, and it is crucial for healthcare providers to monitor the blood concentration levels of the drug at regular intervals. This monitoring is particularly important when patients experience breakthrough seizures, as these episodes may indicate that the therapeutic levels of the medication are insufficient. To perform this test, a blood sample is collected through a procedure known as venipuncture, which is separately reportable. The analysis of the blood serum is conducted using a technique called fluorescence polarization immunoassay, which allows for accurate measurement of the drug levels in the bloodstream.
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The blood test for primidone levels is indicated for several specific clinical scenarios, including:
The procedure for measuring primidone levels involves several key steps, which are outlined as follows:
After the blood sample has been collected and sent for analysis, there are a few considerations for post-procedure care. Patients may experience minor discomfort or bruising at the venipuncture site, which typically resolves on its own. It is advisable for patients to keep the area clean and dry and to apply pressure to the site if bleeding occurs. The healthcare provider may schedule follow-up appointments to discuss the test results and any necessary adjustments to the primidone dosage based on the findings. Regular monitoring of primidone levels is essential for maintaining effective seizure control and ensuring patient safety.
| Short Descr | ASSAY OF PRIMIDONE | Medium Descr | DRUG SCREEN QUANTITATIVE PRIMIDONE | Long Descr | Primidone | 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. | 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. | GW | Service not related to the hospice patient's terminal condition | 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. | 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 |
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| 2013-01-01 | Changed | Medium description changed per AMA 2013 corrections document dated January 25, 2013. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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