2026 ICD-10-CM Diagnosis Code E51Thiamine deficiency

ICD-10-CM Codes›E00–E89›E50-E64›E51

ICD-10-CM E51
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E51 is a non-billable ICD-10-CM category code for thiamine deficiency, so it cannot be submitted on claims. Use a more specific code from this category instead, such as E51.11, E51.12, E51.2, and E51.8.

Code Identity

ICD-10-CM Code
E51
Billable Status
No — Non-Billable Category
Code Describes
Thiamine deficiency
Chapter
E50-E64
Other nutritional deficiencies

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE50-E64Other nutritional deficiencies
CategoryE51Thiamine deficiency
This CodeE51Thiamine deficiency

Specific Coding for Thiamine deficiencyOverview

Non-specific codes like E51 require more characters. Use one of these billable codes instead:

  • E51.1 for Beriberi

  • Use E51.11 for Dry beriberi

  • Use E51.12 for Wet beriberi

  • Use E51.2 for Wernicke's encephalopathy

  • Use E51.8 for Other manifestations of thiamine deficiency

  • Use E51.9 for Thiamine deficiency, unspecified

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Type 1 Excludes

  • sequelae of thiamine deficiency E64.8

Clinical InformationClinical

  • Thiamine Deficiency

    a nutritional condition produced by a deficiency of thiamine in the diet, characterized by anorexia, irritability, and weight loss. later, patients experience weakness, peripheral neuropathy, headache, and tachycardia. in addition to being caused by a poor diet, thiamine deficiency in the united states most commonly occurs as a result of alcoholism, since ethanol interferes with thiamine absorption. in countries relying on polished rice as a dietary staple, beriberi prevalence is very high. (from cecil textbook of medicine, 19th ed, p1171)

Patient EducationClinical

B Vitamins

The B vitamins are:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E51Overview

Is E51 (Thiamine deficiency) a billable code?

No. This is a category header that groups the codes for thiamine deficiency, and headers cannot be submitted on claims. Claims for thiamine deficiency need a more specific code from this category, such as E51.11, E51.12, and E51.2.