HCPCS drug code · CMS crosswalk
Nafcillin J-Code / HCPCS Code
In short
Nafcillin is billed under HCPCS J2291 — Injection, nafcillin sodium (baxter), 20 mg. One billing unit is 20 mg. CMS's crosswalk lists 2 Nafcillin NDCs under this code.
Reference
- J2291
- Injection, nafcillin sodium (baxter), 20 mgBilling unit: 20 mg
- Labelers
- Baxter Healthcare Corporation
Medicare Part B payment limit
CMS ASP filePayment limit per unit$0.135
Per20 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
Nafcillin units and claim line
Enter the dose given to get the J2291 units and the NDC line for the CMS-1500 and the 837P.
Enter the dose given to build the claim line.
Nafcillin NDCs and billing units
From CMS’s ASP NDC–HCPCS crosswalk, effective October 1, 2026 through December 31, 2026. Billing units per package are CMS’s figures for the code’s unit.
| NDC (11-digit) | HCPCS | Labeler | Package | Billing units per package |
|---|---|---|---|---|
| 00338-1017-41 | J2291 | Baxter Healthcare Corporation | 50 | 50 |
| 00338-1019-48 | J2291 | Baxter Healthcare Corporation | 100 | 100 |
Nafcillin: common questions
- What is the J-code for Nafcillin?
- Nafcillin is billed under HCPCS J2291 — Injection, nafcillin sodium (baxter), 20 mg. One billing unit is 20 mg. CMS's crosswalk lists 2 Nafcillin NDCs under this code.
- How many J2291 billing units are in a package of Nafcillin?
- CMS lists 50 to 100 billing units per package, depending on the NDC, where one unit is 20 mg. Units to report are based on the dose given, not the package.
- Is J2291 a CPT code?
- No. J2291 is a HCPCS Level II code from CMS for the drug itself. Giving it, for example by injection or infusion, is usually reported with a separate CPT administration code.