E03.5Myxedema coma

E03.5 is the ICD-10-CM diagnosis code for myxedema coma. It belongs to category E03 (other hypothyroidism), block E00-E07 (disorders of thyroid gland) and chapter 4 (endocrine, nutritional and metabolic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within E03 (other hypothyroidism), E03.5 is specifically for myxedema coma. Related codes cover congenital hypothyroidism with diffuse goiter (E03.0), congenital hypothyroidism without goiter (E03.1), hypothyroidism due to medicaments and other exogenous substances (E03.2), postinfectious hypothyroidism (E03.3), atrophy of thyroid (acquired) (E03.4), other specified hypothyroidism (E03.8) and hypothyroidism, unspecified (E03.9).

As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 080 (Nontraumatic Stupor and Coma with MCC, relative weight 1.7472), DRG 081 (Nontraumatic Stupor and Coma without MCC, relative weight 0.806), DRG 791 (Prematurity with Major Problems, relative weight 4.1075) and DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), in MDC 01 (Diseases and Disorders of the Nervous System) and MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 780.01 (coma).