Lactose intolerance (E73) ICD-10-CM
The E73 code range covers lactose intolerance with 5 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Codes in the E73 Range 5 codes · 4 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the E73 range.
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.
About the E73 Code Range
ICD-10 code E73 covers lactose intolerance, a condition where the body struggles to digest lactose, the sugar found in milk and dairy products. This section includes specific codes that identify different types of lactose intolerance based on cause and onset.
The codes range from E73.0, representing congenital lactase deficiency—a genetic form often called primary lactase deficiency or congenital lactase deficiency—to E73.1, which is used for secondary lactase deficiency, an acquired form that develops due to other diseases affecting the small intestine. Additionally, E73.8 captures other varied types of lactose intolerance, including primary lactose intolerance and hereditary forms, sometimes described as nonpersistence of intestinal lactase or syndromes of carbohydrate intolerance. Lastly, E73.9 is assigned when lactose intolerance is present but unspecified, covering terms such as disaccharidase deficiency or malabsorption syndrome due to lactose intolerance. Utilizing these specific ICD-10 codes helps accurately classify lactose intolerance conditions for clinical documentation and billing purposes.
Questions About This Page
How many billable codes are in the E73 range?
Of the 5 codes in this range, 4 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the E73 range classify?
The range classifies lactose intolerance. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
