No. J9209 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code.

What NDCs are billed under J9209?

CMS's ASP crosswalk for October 1, 2026 through December 31, 2026 lists 7 NDCs under J9209, for Mesna and Mesnex. The table on this page shows each one with its billing units per package.

What is the Medicare payment limit for J9209?

$1.203 per 200 mg, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.

What is one billing unit of J9209?

One unit of J9209 is 200 mg, as stated in the code's descriptor. Units to report = dose given ÷ 200 mg.

J9209 J-Code: Mesnex (mesna) — Billing Units & NDCs

In short

J9209 is the HCPCS Level II code for injection, mesna, 200 mg. CMS assigns NDCs for Mesna and Mesnex to it. One billing unit is 200 mg. The Medicare Part B payment limit is $1.203 per unit (October 1, 2026 through December 31, 2026).

Code

CMS HCPCS file

HCPCS codeJ9209

Billing unit200 mg

Descriptor: Injection, mesna, 200 mg
Short descriptor: Mesna injection
Code set: HCPCS Level II, maintained by CMS
Effective: Jan 1, 2009

The billing unit is read from the descriptor. Confirm it against the CMS file before billing.

Medicare Part B payment limit

CMS ASP file

Payment limit per unit$1.203

Per200 mg

Coinsurance20%

Effective October 1, 2026 through December 31, 2026. Payment allowance limits subject to the ASP methodology are based on 2Q26 ASP data. A payment limit is not a coverage decision; the Medicare contractor decides coverage. CMS ASP pricing files

Units and claim line

Units = dose given ÷ 200 mg. For example, 20000 mg is 100 units. Enter the dose to get the units and the NDC line for the CMS-1500 and the 837P.

Dose given (mg)

HCPCS units (1 unit = 200 mg)

Modifier

NDC (11-digit)

NDC unit qualifier

NDC quantity

Enter the dose given to build the claim line.

NDCs billed under J9209

CMS’s ASP NDC–HCPCS crosswalk (effective October 1, 2026 through December 31, 2026) assigns 7 NDCs to J9209 for Mesna and Mesnex. Billing units per package are CMS’s figures for this code’s unit.

NDCs assigned to J9209 in the CMS ASP crosswalk
Drug	NDC (11-digit)	Labeler	Package	Billing units per package
Mesna	00143-9260-01	Hikma Pharmaceuticals USA Inc.	10	5
Mesna	10019-0953-01	Baxter Healthcare Corporation	10	5
Mesna	25021-0201-10	Sagent Pharmaceuticals	10	5
Mesna	25021-0201-11	Sagent Pharmaceuticals	10 × 10	50
Mesna	63323-0733-11	FreseniUS Kabi USA, LLC	10	5
Mesna	70860-0209-10	Athenex Pharmaceutical Division, LLC	10	5
Mesnex	00338-1305-01	Baxter Healthcare Corporation	10	5

J9209: common questions

Is J9209 a CPT code?: No. J9209 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code. CPT codes for drug administration.
What NDCs are billed under J9209?: CMS's ASP crosswalk for October 1, 2026 through December 31, 2026 lists 7 NDCs under J9209, for Mesna and Mesnex. The table on this page shows each one with its billing units per package.
What is the Medicare payment limit for J9209?: $1.203 per 200 mg, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.
What is one billing unit of J9209?: One unit of J9209 is 200 mg, as stated in the code's descriptor. Units to report = dose given ÷ 200 mg. J-code billing units.

J9209 — Injection, mesna, 200 mg