Summary & Overview
CPT 0054U: AssuranceRx Micro Serum LC–MS/MS Prescription Drug Analysis
CPT code 0054U is a Proprietary Laboratory Analyses (PLA) code for the AssuranceRx Micro Serum assay by Firstox Laboratories, LLC. The test employs chromatography and tandem mass spectrometry (LC–MS/MS) on a capillary blood specimen to detect and quantify prescription medications. As a PLA code, 0054U identifies a single manufacturer-specific diagnostic assay and is used for billing when that specific test is performed.
This code matters nationally because laboratory PLA codes enable payers and providers to track utilization and cost for unique, manufacturer-specific diagnostics that traditional general lab CPT codes do not capture. Key payers analyzed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. These payers have varying policies for coverage of specialized pharmacologic and toxicology testing, which can influence access and reimbursement for assays like AssuranceRx Micro Serum.
Readers will learn the clinical context and service setting for CPT code 0054U, how PLA designations affect billing and tracking, and which national payers are relevant to reimbursement discussions. The publication also covers benchmarks, coding guidance, and policy considerations relevant to proprietary laboratory assays, offering a concise reference for coding, billing, and clinical teams evaluating or ordering this test.
Billing Code Overview
CPT code 0054U is a Proprietary Laboratory Analyses (PLA) code for the AssuranceRx Micro Serum test manufactured by Firstox Laboratories, LLC. The test uses chromatography and tandem mass spectrometry (LC–MS/MS) on a capillary blood specimen to determine the presence or absence and the quantity of prescription drug(s) in a patient’s body.
Service type: Laboratory testing — therapeutic drug monitoring / quantitative prescription drug analysis
Typical site of service: Clinical laboratory or specialty diagnostic laboratory using capillary blood collection (point-of-care collection or outpatient phlebotomy)
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A typical patient scenario involves an outpatient or ambulatory patient undergoing targeted therapeutic drug monitoring or medication adherence testing. A clinician (primary care physician, pain management specialist, addiction medicine clinician, or psychiatrist) orders the AssuranceRx Micro Serum test (0054U) for a patient prescribed controlled or high-risk medications (for example, opioids, benzodiazepines, certain psychiatric medications) to measure the presence and concentration of specified prescription drugs. A small capillary blood specimen is collected (fingerstick) in a clinic, urgent care, behavioral health clinic, or an outpatient laboratory. The specimen is sent to Firstox Laboratories, LLC for proprietary analysis using liquid chromatography–tandem mass spectrometry (LC–MS/MS). Results report presence/absence and quantitative levels of targeted prescription drugs to inform adherence assessment, dose adjustments, safety monitoring, or forensic/medico-legal review. Typical workflow: order placed by the treating clinician, capillary blood collection at point of care, specimen shipped per lab instructions, laboratory performs LC–MS/MS assay, and a report is returned to the ordering clinician for incorporation into clinical decision-making. The test may be performed at outpatient clinics, addiction treatment centers, pain clinics, psychiatric clinics, and independent reference laboratories.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | No modifier; full service | Use when no specific modifier applies and the test is billed as standard. |
26 | Professional component | Use when billing only the professional interpretation component separate from the technical component. |
TC | Technical component | Use when billing only the technical component (laboratory processing) separate from professional interpretation. |
59 | Data not in input — use not allowed per input rules | Data not available in the input. |
52 | Reduced services | Use when the test is partially reduced or not completed as originally intended. |
53 | Discontinued procedure | Use when specimen collection or testing was started but discontinued for patient-related or other valid reasons. |
22 | Increased procedural services | Use when complexity or time is substantially greater than typical for the lab service (rare for PLA tests). |
78 | Unplanned return to operating/procedure room | Not typically applicable to this lab test; retained for completeness. |
80 | Assistant surgeon | Not applicable to this laboratory test but listed among common modifiers. |
QX | Ordering provider modifier (CLIA waived?) | Use when the performing/servicing lab identifies a contractual or ordering-provider relationship per payer-specific rules. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
207Q00000X | Pain Medicine | Common ordering specialty for therapeutic drug monitoring. |
2084P0800X | Addiction Medicine | Frequently orders quantitative drug testing for monitoring adherence and safety. |
2084N0400X | Pain Management | Clinicians in pain clinics commonly order LC–MS/MS prescription drug testing. |
2086S0122X | Psychiatry & Neurology | Psychiatrists may order testing for certain psychiatric medications and adherence. |
207L00000X | Family Medicine | Primary care frequently orders medication adherence testing for chronic therapies. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
F11.20 | Opioid dependence, uncomplicated | Used when monitoring prescribed opioid therapy adherence and safety. |
F13.20 | Sedative, hypnotic or anxiolytic dependence, uncomplicated | Relevant when monitoring benzodiazepine or sedative adherence or misuse. |
F15.20 | Other stimulant dependence, uncomplicated | Applicable when stimulants are prescribed and monitoring or forensic confirmation is required. |
Z51.81 | Encounter for therapeutic drug monitoring | General code indicating encounter specifically for drug level monitoring. |
R78.89 | Other specified abnormal findings of blood chemistry | May be used to document abnormal drug levels identified on testing. |
Z91.19 | Patient's noncompliance with other medical treatment and regimen | Relevant when testing is ordered to assess adherence concerns. |
F10.20 | Alcohol dependence, uncomplicated | Included when polysubstance monitoring or concurrent substance use assessment is relevant. |
Z76.89 | Other persons encountering health services in other specified circumstances | Used in contexts such as pre-procedural testing or medico-legal evaluations where the assay is indicated. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
0054U | AssuranceRx Micro Serum; LC–MS/MS of capillary blood specimen for presence/quantity of prescription drugs (Proprietary Laboratory Analyses) | The billed PLA code describing this specific proprietary assay performed by Firstox Laboratories, LLC. |
80307 | Drug screen, presumptive, any number of drug classes; qualitative, multiple drug classes by immunoassay, capable of presumptive detection of drugs or drug metabolites | Often used as an initial point-of-care or laboratory qualitative screen prior to confirmatory LC–MS/MS quantitative testing. |
80305 | Drug test(s), presumptive, any number of drug classes; screening only, each drug class | Used for single-class presumptive screening when a targeted initial screen precedes definitive LC–MS/MS analysis. |
82570 | Creatinine; urine, for drug testing validity (although urine-specific) | Performed in parallel in workflows that include urine drug testing to assess specimen integrity; indicates multi-modality monitoring strategies. |
80104 | Drug confirmation, quantitative, e.g., by GC/MS, LC/MS/MS (single analyte) | Represents confirmatory quantitative testing by mass spectrometry; clinically related as alternative or complementary confirmatory methodology. |
99000 | Data not in input — use not allowed per input rules | Data not available in the input. |