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N25.1

N25.1Nephrogenic diabetes insipidus

Billable / specific codeICD-10-CM

N25.1 is a billable, specific ICD-10-CM code for nephrogenic diabetes insipidus. It is valid for submission on a claim.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • diabetes insipidus NOS (E23.2)

Other codes that can never be billed with N25.1

These codes carry an Excludes1 note pointing at N25.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading N25.1 alone.

Risk adjustment

N25.1 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

N25.1 is named in 1 Medicare coverage policy 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A57189Billing and Coding: Serum Magnesium

How N25.1 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 N25.1.

  • Diabetes, diabeticinsipidusnephrogenic
  • Diabetes, diabeticinsipidusvasopressin resistant

Related codes at this level

Codes that share N25. If N25.1 is not quite right, the correct code is usually one of these.

Questions about N25.1

Is N25.1 a billable ICD-10-CM code?
Yes. N25.1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does N25.1 sit in the tabular list?
Diseases of the genitourinary system (N00-N99), in the block Other disorders of kidney and ureter (N25-N29).
What cannot be coded together with N25.1?
N25.1 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.