A4321 HCPCS code: Therapeutic agent for urinary catheter irrigation
A4321 is the HCPCS Level II code for therapeutic agent for urinary catheter irrigation. Its Medicare coverage code is D (Special coverage instructions apply): Medicare covers it when its national or local coverage criteria are met. The NCCI unit limit is 1 per day on outpatient hospital claims.
Code details
| Field | Value |
|---|---|
| Section | A codes — Transportation, medical/surgical supplies and miscellaneous |
| Coverage code | D — Special coverage instructions apply |
| Pricing indicator | 37 — DMEPOS: ostomy, tracheostomy and urological supplies |
| BETOS category | D1F — Prosthetic and orthotic devices |
| Added | 1997-01-01 |
| Last action effective | 2003-01-01 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| outpatient hospital claims | 1 | Code Descriptor / CPT Instruction |
| practitioner claims | 1 | Code Descriptor / CPT Instruction |
Medicare policy articles for this code
- A52521: Urological Supplies - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance
Covered diagnoses (1 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| N39.3 | Stress incontinence (female) (male) | 1 |
What changed for A4321
- 1997-01-01: A4321 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code A4321?
A4321 is the HCPCS Level II code for therapeutic agent for urinary catheter irrigation. Short descriptor: "Cath therapeutic irrig agent".
Does Medicare cover A4321?
Coverage code D — Special coverage instructions apply. Medicare covers it when its national or local coverage criteria are met.
Which diagnoses support coverage for A4321?
Medicare policy articles that cite A4321 list 1 covered ICD-10-CM diagnosis codes across 1 article. The most cited include N39.3 (Stress incontinence (female) (male)). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.
How many units of A4321 can be billed per day?
1 on outpatient hospital claims; 1 on practitioner claims (NCCI medically unlikely edits).
Related A43 codes
- A4300 — Implantable access catheter, (e.g., venous, arterial, epidural subarachnoid, or peritoneal, etc.) external access
- A4301 — Implantable access total catheter, port/reservoir (e.g., venous, arterial, epidural, subarachnoid, peritoneal, etc.)
- A4305 — Disposable drug delivery system, flow rate of 50 ml or greater per hour
- A4306 — Disposable drug delivery system, flow rate of less than 50 ml per hour
- A4310 — Insertion tray without drainage bag and without catheter (accessories only) ($9.36–$25.22)
- A4311 — Insertion tray without drainage bag with indwelling catheter, foley type, two-way latex with coating (teflon, silicone, silicone elastomer or hydrophilic, etc.) ($16.05–$28.00)
- A4312 — Insertion tray without drainage bag with indwelling catheter, foley type, two-way, all silicone ($21.85–$36.59)
- A4313 — Insertion tray without drainage bag with indwelling catheter, foley type, three-way, for continuous irrigation ($22.44–$40.49)
- A4314 — Insertion tray with drainage bag with indwelling catheter, foley type, two-way latex with coating (teflon, silicone, silicone elastomer or hydrophilic, etc.) ($30.63–$41.77)
- A4315 — Insertion tray with drainage bag with indwelling catheter, foley type, two-way, all silicone ($31.95–$48.37)
- A4316 — Insertion tray with drainage bag with indwelling catheter, foley type, three-way, for continuous irrigation ($34.40–$48.37)
- A4318 — Female external urinary collection cup, with or without ring attachment, per day
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Next steps
- Run a reimbursement report for a device billed under A4321
- Watch A4321 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A4321
Sources: CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.