G9143 — Warfarin responsiveness testing by genetic technique using any method, any number of specimen(s)
G9143 is a HCPCS Level II code for warfarin responsiveness testing by genetic technique using any method, any number of specimen(s). It belongs to the Procedures and Professional Services (Temporary) section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Physician fee schedule statusX
Statutory exclusion. The item or service is not within the statutory definition of 'physician services', so the fee schedule never pays it.
Global period: XXX
Want the dollar amount for your locality? The fee calculator applies your GPCI and the current conversion factor.
Medically Unlikely Edits — units per day
The most units of G9143 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 1 unit MAI 2 — Date of Service Edit: Policy · Code Descriptor / CPT Instruction
- outpatient
- 1 unit MAI 2 — Date of Service Edit: Policy · Code Descriptor / CPT Instruction
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for G9143
- Long descriptor
- Warfarin responsiveness testing by genetic technique using any method, any number of specimen(s)
- Short descriptor
- Warfarin respon genetic test
- Added
- August 3, 2009
- BETOS
- M5D
- Pricing indicator
- 13 — Physician fee schedule
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Price established by carriers — not otherwise classified, individual determination, or carrier discretion.
Codes adjacent to G9143
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If G9143 is not quite right, the correct code is very often within a few positions of it.
- G9133Oncology; disease status; prostate cancer, limited to adenocarcinoma; hormone-responsive; clinical metastases or m1 at diagnosis (for use in a medicare-approved demonstration project)
- G9134Oncology; disease status; non-hodgkin's lymphoma, any cellular classification; stage i, ii at diagnosis, not relapsed, not refractory (for use in a medicare-approved demonstration project)
- G9135Oncology; disease status; non-hodgkin's lymphoma, any cellular classification; stage iii, iv, not relapsed, not refractory (for use in a medicare-approved demonstration project)
- G9136Oncology; disease status; non-hodgkin's lymphoma, transformed from original cellular diagnosis to a second cellular classification (for use in a medicare-approved demonstration project)
- G9137Oncology; disease status; non-hodgkin's lymphoma, any cellular classification; relapsed/refractory (for use in a medicare-approved demonstration project)
- G9138Oncology; disease status; non-hodgkin's lymphoma, any cellular classification; diagnostic evaluation, stage not determined, evaluation of possible relapse or non-response to therapy, or not listed (for use in a medicare-approved demonstration project)
- G9139Oncology; disease status; chronic myelogenous leukemia, limited to philadelphia chromosome positive and/or bcr-abl positive; extent of disease unknown, staging in progress, not listed (for use in a medicare-approved demonstration project)
- G9140Frontier extended stay clinic demonstration; for a patient stay in a clinic approved for the cms demonstration project; the following measures should be present: the stay must be equal to or greater than 4 hours; weather or other conditions must prevent transfer or the case falls into a category of monitoring and observation cases that are permitted by the rules of the demonstration; there is a maximum frontier extended stay clinic (fesc) visit of 48 hours, except in the case when weather or other conditions prevent transfer; payment is made on each period up to 4 hours, after the first 4 hours
- G9147Outpatient intravenous insulin treatment (oivit) either pulsatile or continuous, by any means, guided by the results of measurements for: respiratory quotient; and/or, urine urea nitrogen (uun); and/or, arterial, venous or capillary glucose; and/or potassium concentration
- G9148National committee for quality assurance - level 1 medical home
- G9149National committee for quality assurance - level 2 medical home
- G9150National committee for quality assurance - level 3 medical home
- G9151Mapcp demonstration - state provided services
- G9152Mapcp demonstration - community health teams
- G9153Mapcp demonstration - physician incentive pool
- G9156Evaluation for wheelchair requiring face to face visit with physician
Questions about G9143
What is HCPCS code G9143?
G9143 is a HCPCS Level II code for warfarin responsiveness testing by genetic technique using any method, any number of specimen(s). It sits in the Procedures and Professional Services (Temporary) section.
Does Medicare cover G9143?
The CMS HCPCS file marks G9143 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
How is G9143 paid under the physician fee schedule?
G9143 carries PFS status code X. Statutory exclusion. The item or service is not within the statutory definition of 'physician services', so the fee schedule never pays it.