A4774 — Ammonia test strips, for dialysis, per 50
A4774 is a HCPCS Level II code for ammonia test strips, for dialysis, per 50. It belongs to the Transportation, Medical & Surgical Supplies, Administrative section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Special coverage instructions apply
There are published conditions attached to this code. Check the applicable coverage policy before billing it: the code being valid is not the same as the service being covered.
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 A4774 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
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- DME supplier
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
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 A4774
- Long descriptor
- Ammonia test strips, for dialysis, per 50
- Short descriptor
- Ammonia test strips
- Added
- January 1, 1986
- BETOS
- P9B
- Pricing indicator
- 00 — Not priced by Part B
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.
Service not separately priced by Part B — not covered, bundled into another service, or used by Part A only.
Codes adjacent to A4774
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If A4774 is not quite right, the correct code is very often within a few positions of it.
- A4755Blood tubing, arterial and venous combined, for hemodialysis, each
- A4760Dialysate solution test kit, for peritoneal dialysis, any type, each
- A4765Dialysate concentrate, powder, additive for peritoneal dialysis, per packet
- A4766Dialysate concentrate, solution, additive for peritoneal dialysis, per 10 ml
- A4770Blood collection tube, vacuum, for dialysis, per 50
- A4771Serum clotting time tube, for dialysis, per 50
- A4772Blood glucose test strips, for dialysis, per 50
- A4773Occult blood test strips, for dialysis, per 50
- A4802Protamine sulfate, for hemodialysis, per 50 mg
- A4860Disposable catheter tips for peritoneal dialysis, per 10
- A4870Plumbing and/or electrical work for home hemodialysis equipment
- A4890Contracts, repair and maintenance, for hemodialysis equipment
- A4911Drain bag/bottle, for dialysis, each
- A4913Miscellaneous dialysis supplies, not otherwise specified
- A4918Venous pressure clamp, for hemodialysis, each
- A4927Gloves, non-sterile, per 100
Questions about A4774
What is HCPCS code A4774?
A4774 is a HCPCS Level II code for ammonia test strips, for dialysis, per 50. It sits in the Transportation, Medical & Surgical Supplies, Administrative section.
Does Medicare cover A4774?
The CMS HCPCS file marks A4774 as "Special coverage instructions apply". There are published conditions attached to this code. Check the applicable coverage policy before billing it: the code being valid is not the same as the service being covered.
How is A4774 paid under the physician fee schedule?
A4774 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.