2027 ICD-10-CM Diagnosis Code E73Lactose intolerance

ICD-10-CM Codes›E00–E89›E70-E88›E73

ICD-10-CM E73
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

E73 is a non-billable ICD-10-CM category code for lactose intolerance, so it cannot be submitted on claims. Use a more specific code from this category instead, such as E73.0, E73.1, E73.8, and E73.9.

Code Identity

ICD-10-CM Code
E73
Billable Status
No — Non-Billable Category
Code Describes
Lactose intolerance
Short Description
Lactose intolerance
Same as the full description in the CMS dataset.
Chapter
E70-E88
Metabolic disorders

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE70-E88Metabolic disorders
CategoryE73Lactose intolerance
This CodeE73Lactose intolerance

Specific Coding for Lactose intoleranceOverview

Non-specific codes like E73 require more characters. Use one of these billable codes instead:

  • Use E73.0 for Congenital lactase deficiency

  • Use E73.1 for Secondary lactase deficiency

  • Use E73.8 for Other lactose intolerance

  • Use E73.9 for Lactose intolerance, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to E73: its own notes plus those printed at block E70-E88 and Chapter 4. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block E70-E88 Metabolic disorders applies to 286 codes
  • androgen insensitivity syndrome (E34.5-)
  • congenital adrenal hyperplasia (E25.0)
  • hemolytic anemias attributable to enzyme disorders (D55.-)
  • Marfan syndrome (Q87.4-)
  • 5-alpha-reductase deficiency (E29.1)
From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • transitory endocrine and metabolic disorders specific to newborn (P70-P74)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Block E70-E88 Metabolic disorders applies to 286 codes
  • Ehlers-Danlos syndromes (Q79.6-)

Notes

General instructions on how these codes are used.

From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name E73, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming E73: they are not reported together with it, unless the two conditions are unrelated.

  • R79 Other abnormal findings of blood chemistry
    specific findings indicating disorder of carbohydrate metabolism (E73-E74)
  • Block R80-R82 Abnormal findings on examination of urine, without diagnosis
    specific findings indicating disorder of carbohydrate metabolism (E73-E74)
  • Z91.011 Allergy to milk products
    lactose intolerance (E73.-)

Excludes2 2

These codes carry an Excludes2 note naming E73: its condition is not part of those codes, and both may be reported when the patient has both.

  • E74.3 Other disorders of intestinal carbohydrate absorption
    lactose intolerance (E73.-)
  • K90.4 Other malabsorption due to intolerance
    lactose intolerance (E73.-)

Clinical InformationClinical

  • Lactose Intolerance

    the condition resulting from the absence or deficiency of lactase in the mucosa cells of the gastrointestinal tract, and the inability to break down lactose in milk for absorption. bacterial fermentation of the unabsorbed lactose leads to symptoms that range from a mild indigestion (dyspepsia) to severe diarrhea. lactose intolerance may be an inborn error or acquired.

Patient EducationClinical

Lactose Intolerance

Lactose intolerance means that you cannot digest foods with lactose in them. Lactose is the sugar found in milk and foods made with milk. After eating foods with lactose in them, you may feel sick to your stomach. You may also have:

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About E73Overview

What is the ICD-10 code for lactose intolerance?

E73 is the ICD-10-CM category for lactose intolerance, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is E73 (Lactose intolerance) a billable code?

No. This is a category header that groups the codes for lactose intolerance, and headers cannot be submitted on claims. Claims for lactose intolerance need a more specific code from this category, such as E73.0, E73.1, and E73.8.

Can E73 be reported with a code from E34.5?

Not as a rule. The Excludes1 note at block E70-E88, which applies to E73, lists "androgen insensitivity syndrome (E34.5-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).