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I73.81

I73.81Erythromelalgia

Billable / specific codeICD-10-CM

I73.81 is a billable, specific ICD-10-CM code for erythromelalgia. It is valid for submission on a claim.

Excludes1 inherited from the categories above I73.81

These are not written on I73.81, but they bind it: a note on a category applies to every code beneath it. Billing I73.81 with anything listed here is a denial.

Written on I73.8 Other specified peripheral vascular diseases

  • diabetic (peripheral) angiopathy (E08-E13 with .51-.52)

Excludes2 inherited from the categories above I73.81

Also inherited, and the opposite of Excludes1: these conditions are not part of I73.81, but a patient can have both, so you may code both.

Written on I73 Other peripheral vascular diseases

Other codes that can never be billed with I73.81

These codes carry an Excludes1 note pointing at I73.81. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading I73.81 alone.

  • I96Gangrene, not elsewhere classified

Risk adjustment

I73.81 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

I73.81 is named in 4 Medicare coverage policies 4 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A52996Billing and Coding: Routine Foot Care
  • A56775Billing and Coding: Magnetic Resonance Angiography
  • A57193Billing and Coding: Routine Foot Care and Debridement of Nails
  • A57759Billing and Coding: Routine Foot Care and Debridement of Nails

How I73.81 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 I73.81.

  • Acromelalgia
  • Erythermalgia(primary)
  • Erythralgia
  • Erythromelalgia
  • Mitchell's disease(erythromelalgia)
  • Weir Mitchell's disease
  • Disease, diseasedGerhardt's(erythromelalgia)
  • Disease, diseasedMitchell's(erythromelalgia)
  • Disease, diseasedWeir Mitchell's(erythromelalgia)
  • Gerhardt'sdisease(erythromelalgia)

Code history

I73.81 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share I73.8. If I73.81 is not quite right, the correct code is usually one of these.

Questions about I73.81

Is I73.81 a billable ICD-10-CM code?
Yes. I73.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does I73.81 sit in the tabular list?
Diseases of the circulatory system (I00-I99), in the block Diseases of arteries, arterioles and capillaries (I70-I79).
What cannot be coded together with I73.81?
I73.81 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above I73.81 (I73.8) and apply to it just the same.
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.