ICD-10-CM 2027
ICD-10 code for methemoglobinemia
From the official ICD-10-CM alphabetic index entry “Methemoglobinemia”. Page updated September 29, 2026.
About coding methemoglobinemia
The ICD-10-CM code for methemoglobinemia is D74.9 (Methemoglobinemia, unspecified). The official index lists 6 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on D74.9.
Within D74, choose D74.9 (unspecified) only when documentation doesn't support a more specific option: congenital methemoglobinemia (D74.0) and other methemoglobinemias (D74.8).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" 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 811 (Red Blood Cell Disorders with MCC, relative weight 1.3988) and DRG 812 (Red Blood Cell Disorders without MCC, relative weight 0.9234), in MDC 16 (Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific methemoglobinemia codes (official index)
- acquired (with sulfhemoglobinemia) D74.8 — Other methemoglobinemias
- congenital D74.0 — Congenital methemoglobinemia
- enzymatic (congenital) D74.0 — Congenital methemoglobinemia
- Hb M disease D74.0 — Congenital methemoglobinemia
- hereditary D74.0 — Congenital methemoglobinemia
- toxic D74.8 — Other methemoglobinemias
Common questions about methemoglobinemia ICD-10 codes
What is the ICD-10 code for methemoglobinemia?
- D74.9 — Methemoglobinemia, unspecified. More specific codes apply when the documentation supports them: D74.8, D74.0, D74.0, D74.0 and others below.
What is the ICD-10 code for acquired methemoglobinemia?
- D74.8 — Other methemoglobinemias.
What is the ICD-10 code for congenital methemoglobinemia?
- D74.0 — Congenital methemoglobinemia.
What is the ICD-10 code for enzymatic methemoglobinemia?
- D74.0 — Congenital methemoglobinemia.
What is the ICD-10 code for hb m disease methemoglobinemia?
- D74.0 — Congenital methemoglobinemia.
What is the ICD-10 code for hereditary methemoglobinemia?
- D74.0 — Congenital methemoglobinemia.
What is the ICD-10 code for toxic methemoglobinemia?
- D74.8 — Other methemoglobinemias.
Is D74.9 billable?
- Yes. D74.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can D74.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict D74.9 as a principal diagnosis.
Is D74.9 a CC or MCC?
- D74.9 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.