Billing code 11901: Lesion injectionMedicare rate & RVUs in Washington
Report this service when a clinician injects intralesional medication into more than seven discrete skin lesions during one treatment session.
Medicare pays $70.73–$78.85 for 11901 in the office in Washington, from Rest Of Washington to Seattle (King Cnty). Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 11901 covers
Code 11901 represents the clinician’s work injecting medication directly into more than seven discrete skin lesions in one treatment session. Dermatologists commonly use intralesional corticosteroid injections for multiple keloids or hypertrophic scars. The clinician identifies the target lesions and places the medication within them, rather than injecting a subcutaneous filling material for volume correction.
Select 11901 by the number of lesions actually injected: more than seven qualifies, while 11900 covers up to seven. Document the lesion count and locations, indication, agent and amount, and injection service. This code has a 0-day global period, so same-day preoperative and postoperative care is included. When another procedure is performed in the same session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% multiple-procedure reduction. Modifier 50 is inappropriate. Assistant-at-surgery payment is statutorily restricted, and co-surgeon and team-surgery billing are not permitted.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 11901 pays more and less in Washington
| Payment locality | Office | Facility |
|---|---|---|
| Rest Of Washington | $70.73 | $36.61 |
| Seattle (King Cnty) | $78.85 | $39.10 |
How the 11901 rate is calculated
Each of 11901’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 11901
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 0.78Practice expense 1.21Malpractice 0.07
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 11901
The CMS indicators that decide how 11901 is paid alongside other services.
CMS payment indicators · 11901
Lesion injection
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
11901 without 51 · national office
$68.81
Lesion injection
11901-51 · Second procedure: 50%
$34.41
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
11901 compared with similar codes
Compare codes
11901 vs 11900 vs 11950 vs 11920: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 11900Lesion injection
- Use 11900 when up to seven lesions are injected. Use 11901 when more than seven are injected in the session.
- 11950Subq njx filling matrl 1cc/<
- 11901 describes medication injected into skin lesions. 11950 describes subcutaneous injection of filling material, selected by the material volume.
- 11920Correct skin color 6.0 cm/<
- 11920 is for correction of skin color by tattooing, measured by treated area. 11901 is for intralesional medication injection, counted by lesions.
11901 billing questions
When should 11901 be chosen instead of 11900?
Count the discrete lesions actually injected during the treatment session. Use 11901 for more than seven lesions; 11900 covers up to seven.
Is the code reported once per lesion or once per session?
Choose the code level based on the total number of lesions injected in the session. Do not report one unit for each lesion or needle pass.
Can the medication be billed separately?
The procedure code represents the intralesional injection service, not the medication product. Report a separately identifiable drug product under the applicable drug coding rules when eligible.
Can modifier 50 be used for lesions on both sides?
No. Bilateral adjustment does not apply to this code, and modifier 50 is inappropriate.
What same-day care is included?
The code has a 0-day global period, so same-day preoperative and postoperative care is included. A separately identifiable evaluation may be reported when its documentation supports a distinct E/M service.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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