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The CPT® Code 80170 refers to the laboratory test for measuring gentamicin levels in the blood. Gentamicin is an injectable aminoglycoside antibiotic, commonly known by its brand names such as Garamycin, Cidomycin, or Septopal. This medication is primarily prescribed for the treatment of severe or serious bacterial infections. Due to its potential side effects, which include auditory, vestibular, and renal toxicity, monitoring the blood levels of gentamicin is crucial. The test is designed to assess gentamicin concentrations at various times, specifically at random, peak, and trough intervals. A random sample can be collected at any time, while peak and trough levels are dependent on specific timing related to the administration of the drug. Typically, trough levels are drawn 30 minutes before the next dose of gentamicin, either through intravenous infusion or intramuscular injection. Conversely, peak levels are collected 15 to 30 minutes after the completion of an intravenous infusion or 90 minutes following an intramuscular injection. The blood sample for this test is obtained through a venipuncture, which is a separately reportable procedure. The analysis of the blood serum is conducted using a fluorescence polarization immunoassay, a method that allows for accurate measurement of the drug levels in the bloodstream.
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The gentamicin blood test (CPT® Code 80170) is indicated for the following conditions:
The procedure for measuring gentamicin levels involves several key steps that ensure accurate and reliable results. First, a blood sample is obtained through venipuncture, which is the process of puncturing a vein to draw blood. This step is crucial as it provides the serum needed for testing. Once the blood is collected, the timing of the sample is critical for peak and trough level measurements. A trough level is drawn 30 minutes prior to the next scheduled dose of gentamicin, which can be administered either intravenously or intramuscularly. This timing helps to determine the lowest concentration of the drug in the bloodstream before the next dose is given. In contrast, a peak level is collected 15 to 30 minutes after the completion of an intravenous infusion or 90 minutes after an intramuscular injection. This timing is essential to assess the highest concentration of gentamicin in the blood following administration. After the samples are collected, they are analyzed using a fluorescence polarization immunoassay, a sophisticated laboratory technique that allows for precise measurement of gentamicin levels in the serum.
After the blood sample has been collected for gentamicin level testing, there are no specific post-procedure care requirements mentioned. However, it is important for healthcare providers to monitor the patient for any signs of toxicity, especially if the gentamicin levels are found to be elevated. Regular follow-up and additional testing may be necessary to ensure that the patient remains within the therapeutic range and to adjust dosages as needed based on the test results. Continuous assessment of renal function and auditory health may also be warranted, given the potential side effects associated with gentamicin therapy.
| Short Descr | ASSAY OF GENTAMICIN | Medium Descr | DRUG SCREEN QUANTITATIVE GENTAMICIN | Long Descr | Gentamicin | 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 | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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. | 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. | 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 | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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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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