ICD10BillableValid for clinical use

ICD-10 Code D51.9: Vitamin B12 deficiency anemia, unspecified

D51.9 is a billable ICD-10 diagnosis code used to classify Vitamin B12 deficiency anemia, unspecified in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89).

Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026

What is this code?

ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89).

When is it used?

  • May be used when a clinician documents vitamin b12 deficiency anemia, unspecified in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code can be used as a clinically usable diagnosis entry in standardized coding workflows.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.

Code hierarchy

chapter
3Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)
block
D50-D53Nutritional anemias
category
D51Vitamin B12 deficiency anemia
currentD51

Where you may see this code

You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.

Related specialists

HematologistGeneral Physician

Coding guidelines

Compatibility

Legacy and official ICD code match exactly.
Legacy codes
D51.9

Common synonyms

Vitamin B12 deficiency anemia, unspecifiedVitamin B12 deficiency anemia

Frequently asked questions

Code details

CodeD51.9
SystemICD10
Display nameVitamin B12 deficiency anemia, unspecified
ChapterDiseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)
BlockNutritional anemias

Flags

BillableYes
Valid clinical useYes

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

Index terms

Matched terms
Anemia(essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound)Degeneration, degenerative

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

ICD-10 Code D51.9 for Vitamin B12 deficiency anemia, unspecified | HealthAssure