N23 — Unspecified renal colic
N23 is a billable, specific ICD-10-CM code for unspecified renal colic. It is valid for submission on a claim.
Other codes that can never be billed with N23
These codes carry an Excludes1 note pointing at N23. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading N23 alone.
Risk adjustment
N23 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
N23 is named in 2 Medicare coverage policies — 2 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A55336Billing and Coding: Retroperitoneal Ultrasound
- A56421Billing and Coding: CT of the Abdomen and Pelvis
How N23 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to N23.
- Nephralgia
- Ureteralgia
- Colic›kidney
- Colic›nephritic
- Colic›renal
- Colic›ureter
- Pain›kidney
- Pain›ureter
- Pain›urinary(organ) (system)
Questions about N23
- Is N23 a billable ICD-10-CM code?
- Yes. N23 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does N23 sit in the tabular list?
- Diseases of the genitourinary system (N00-N99), in the block Urolithiasis (N20-N23).