2022 ICD-10-CM Code E73

Lactose intolerance

Version 2021

Not Valid for Submission

ICD-10:E73
Short Description:Lactose intolerance
Long Description:Lactose intolerance

Code Classification

  • Endocrine, nutritional and metabolic diseases (E00–E90)
    • Metabolic disorders (E70-E88)
      • Lactose intolerance (E73)

E73 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of lactose intolerance. The code is not specific and is NOT valid for the year 2022 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding for Lactose intolerance

Non-specific codes like E73 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for lactose intolerance:

  • BILLABLE CODE - Use E73.0 for Congenital lactase deficiency
  • BILLABLE CODE - Use E73.1 for Secondary lactase deficiency
  • BILLABLE CODE - Use E73.8 for Other lactose intolerance
  • BILLABLE CODE - Use E73.9 for Lactose intolerance, unspecified

Clinical Information

Information for Patients


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

Your doctor may do a blood, breath or stool test to find out if your problems are due to lactose intolerance.

Lactose intolerance is not serious. Eating less food with lactose, or using pills or drops to help you digest lactose usually helps. You may need to take a calcium supplement if you don't get enough of it from your diet, since milk and foods made with milk are the most common source of calcium for most people.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


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Lactose intolerance

Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine.

Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss.

Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later.

Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk.


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)