MCMedicalCodingSoftware
E03.5

E03.5: Myxedema coma

Billable / specific codeICD-10-CM

E03.5 is a billable, specific ICD-10-CM code for myxedema coma. It is valid for submission on a claim.

Check E03.5 with the rest of the claim: free scrubber

Excludes1 inherited from the categories above E03.5

A category’s note binds every code beneath it.

Written on E03: Other hypothyroidism

  • iodine-deficiency related hypothyroidism (E00-E02)
  • postprocedural hypothyroidism (E89.0)

Risk adjustment

E03.5 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

  • HCC 202 Coma, Brain Compression/Anoxic Damage0.543 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score. Look up the whole chart to see which of its HCCs the hierarchy would zero.

Medicare coverage

E03.5 is named in 11 Medicare coverage policies: 11 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.

  • A56612Billing and Coding: CT of the Head
  • A56645Billing and Coding: Controlled Substance Monitoring and Drugs of Abuse Testing
  • A56773Billing and Coding: Neurophysiology Evoked Potentials (NEPs)
  • A56781Billing and Coding: Transthoracic Echocardiography (TTE)

Alphabetic index entries that lead here

  • Coma›myxedematous
  • Myxedema›coma

Code history

Unchanged in every release from FY2024 to FY2027.

Other codes under E03

ICD-10-CMFY2027· effective October 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.