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The CPT® Code 80184 refers to a laboratory test specifically designed to measure the levels of phenobarbital in the blood. Phenobarbital, which is also known by its brand name Luminal, is classified as an anticonvulsant and hypnotic medication. It is primarily prescribed for the management of seizures and the treatment of insomnia. The mechanism of action involves the reduction of electrical activity in the brain, which helps to stabilize neuronal excitability and prevent seizure episodes. The administration of phenobarbital can occur through oral ingestion or via injection, depending on the clinical scenario and patient needs. Regular monitoring of blood concentration levels is essential, particularly during treatment, as it helps to ensure that the drug remains within therapeutic ranges. This monitoring is especially critical when patients experience breakthrough seizure activity or signs of oversedation, which may indicate that the blood levels of phenobarbital are either too high or too low. To perform this test, a blood sample is collected through a procedure known as venipuncture, which is separately reportable. Following the collection, the serum is analyzed using high-performance liquid chromatography, a sophisticated technique that allows for precise measurement of the drug concentration in the blood.
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The phenobarbital blood test (CPT® Code 80184) is indicated for several specific clinical scenarios, including:
The procedure for obtaining a phenobarbital level 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 important for healthcare providers to inform patients about potential signs of complications, such as excessive bleeding or infection at the site. Additionally, once the test results are available, healthcare providers will review the phenobarbital levels and make any necessary adjustments to the patient's medication regimen based on the findings. Regular follow-up appointments may be scheduled to continue monitoring the patient's response to treatment and to ensure optimal therapeutic outcomes.
| Short Descr | ASSAY OF PHENOBARBITAL | Medium Descr | DRUG SCREEN QUANTITATIVE PHENOBARBITAL | Long Descr | Phenobarbital | 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. | 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. | GW | Service not related to the hospice patient's terminal condition | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | 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 | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | GZ | Item or service expected to be denied as not reasonable and necessary |
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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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