Summary & Overview
CPT 80171: Gabapentin Quantitative Assay in Blood/Serum/Plasma
CPT code 80171 denotes a quantitative assay for gabapentin in blood, serum, or plasma. This laboratory test supports therapeutic drug monitoring and clinical decision-making for patients treated with gabapentin, commonly prescribed for certain seizure disorders and neuropathic pain. Nationally, standardized coding for drug assays like 80171 matters for consistent clinical communication, claims processing, and quality measurement across inpatient and outpatient laboratory settings.
Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical purpose and service settings for 80171, typical billing considerations, and where this service sits within laboratory and therapeutic monitoring workflows. The publication summarizes common modifiers and operational notes where available, benchmarks and reimbursement context when provided, and links to related laboratory coding considerations.
The content is intended to give clinicians, laboratory managers, and billing professionals a clear, national-level overview of what CPT code 80171 represents, why it is used, and which payers commonly cover such testing. Data not available in the input is noted where applicable.
Billing Code Overview
CPT code 80171 measures the amount of gabapentin in a patient's blood, serum, or plasma. The test quantifies gabapentin levels to inform clinical management of patients receiving gabapentin for seizure disorders and other indications.
Service type: Therapeutic drug monitoring / quantitative drug assay
Typical site of service: Clinical laboratory (hospital laboratory, independent reference lab, or outpatient phlebotomy collection site)
Clinical & Coding Specifications
Clinical Context
A 34-year-old patient with a history of focal epilepsy is managed in an outpatient neurology clinic. The treating neurologist prescribes gabapentin for seizure control and schedules periodic therapeutic drug monitoring to confirm adherence and to ensure serum concentrations are within the expected range for clinical effect and safety. The patient presents to the outpatient laboratory for a blood draw. A phlebotomist collects a serum sample, which is sent to the clinical chemistry laboratory. The lab analyst performs quantitative measurement of gabapentin in the serum using a validated assay (e.g., liquid chromatography–mass spectrometry or immunoassay), documents the result in the laboratory information system, and reports the value to the ordering clinician. Results are used by the neurologist to adjust gabapentin dosing, evaluate potential toxicity, or assess adherence when seizures are not controlled.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | No modifier; standard reporting | Use when no special modifier applies to the service. |
11 | Critical care or primary service? (Note: not a CMS standard for this context; included per input) | Use only if billing system requires a specific primary service indicator—rare for lab billing. |