ICD-10 Code D74.0 – Congenital methemoglobinemia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D74.0 – Congenital methemoglobinemia
What it is
Congenital methemoglobinemia is an inherited disorder that causes hemoglobin to stay in the methemoglobin form, which cannot carry oxygen normally. Use this code when documentation identifies the congenital condition.
Clinical signs
Typical findings include persistent cyanosis, low oxygen saturation that may not improve as expected, and possible shortness of breath or fatigue. Clinical features vary; refer to documentation.
When to use this code
Use D74.0 when the provider documents congenital methemoglobinemia, hereditary methemoglobinemia, or an inherited methemoglobin-reduction defect. It may also apply when the condition is confirmed during evaluation of unexplained cyanosis. Do not infer it from a single abnormal test without documentation.
Do not use for
Do not use this code for acquired methemoglobinemia from drugs, chemicals, or other exposures. If the cause is unclear, check documentation before coding.
Coding tip
Look for wording that confirms the disorder is congenital or hereditary, not just methemoglobinemia.