2024 ICD-10-CM Diagnosis Code Z91.011

Allergy to milk products

ICD-10-CM Code:
Z91.011
ICD-10 Code for:
Allergy to milk products
Is Billable?
Yes - Valid for Submission
Code Navigator:

Code Classification

  • Factors influencing health status and contact with health services
    (Z00–Z99)
    • Persons with potential health hazards related to family and personal history and certain conditions influencing health status
      (Z77-Z99)
      • Personal risk factors, not elsewhere classified
        (Z91)

Z91.011 is a billable diagnosis code used to specify a medical diagnosis of allergy to milk products. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024. The code is exempt from present on admission (POA) reporting for inpatient admissions to general acute care hospitals.

This code describes a circumstance which influences the patient's health status but not a current illness or injury. The code is unacceptable as a principal diagnosis.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Allergy to casein
  • Allergy to cattle protein
  • Allergy to cheese
  • Allergy to cow's milk protein
  • Hemosiderosis
  • Milk-induced pulmonary disease in infant
  • Secondary hemosiderosis
  • Secondary pulmonary hemosiderosis

Clinical Classification

Clinical Information

  • Hemosiderosis

    conditions in which there is a generalized increase in the iron stores of body tissues, particularly of liver and the mononuclear phagocyte system, without demonstrable tissue damage. the name refers to the presence of stainable iron in the tissue in the form of hemosiderin.
  • Mononuclear Phagocyte System

    mononuclear cells with pronounced phagocytic ability that are distributed extensively in lymphoid and other organs. it includes macrophages and their precursors; phagocytes; kupffer cells; histiocytes; dendritic cells; langerhans cells; and microglia. the term mononuclear phagocyte system has replaced the former reticuloendothelial system, which also included less active phagocytic cells such as fibroblasts and endothelial cells. (from illustrated dictionary of immunology, 2d ed.)

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • lactose intolerance E73

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • Unacceptable principal diagnosis - There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Present on Admission (POA)

Z91.011 is exempt from POA reporting - The Present on Admission (POA) indicator is used for diagnosis codes included in claims involving inpatient admissions to general acute care hospitals. POA indicators must be reported to CMS on each claim to facilitate the grouping of diagnoses codes into the proper Diagnostic Related Groups (DRG). CMS publishes a listing of specific diagnosis codes that are exempt from the POA reporting requirement. Review other POA exempt codes here.

CMS POA Indicator Options and Definitions

POA IndicatorReason for CodeCMS will pay the CC/MCC DRG?
YDiagnosis was present at time of inpatient admission.YES
NDiagnosis was not present at time of inpatient admission.NO
UDocumentation insufficient to determine if the condition was present at the time of inpatient admission.NO
WClinically undetermined - unable to clinically determine whether the condition was present at the time of inpatient admission.YES
1Unreported/Not used - Exempt from POA reporting. NO

Convert Z91.011 to ICD-9-CM

  • ICD-9-CM Code: V15.02 - Hx-milk prod allergy

Patient Education


Food Allergy

Food allergy is an abnormal response to a food triggered by your body's immune system.

In adults, the foods that most often trigger allergic reactions include fish, shellfish, peanuts, and tree nuts, such as walnuts. Problem foods for children can include eggs, milk, peanuts, tree nuts, soy, and wheat.

The allergic reaction may be mild. In rare cases it can cause a severe reaction called anaphylaxis. Symptoms of food allergy include:

  • Itching or swelling in your mouth
  • Vomiting, diarrhea, or abdominal cramps and pain
  • Hives or eczema
  • Tightening of the throat and trouble breathing
  • Drop in blood pressure

Your health care provider may use a detailed history, elimination diet, and skin and blood tests to diagnose a food allergy.

When you have food allergies, you must be prepared to treat an accidental exposure. Wear a medical alert bracelet or necklace, and carry an auto-injector device containing epinephrine (adrenaline).

You can only prevent the symptoms of food allergy by avoiding the food. After you and your health care provider have identified the foods to which you are sensitive, you must remove them from your diet.


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • 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. This was the first year ICD-10-CM was implemented into the HIPAA code set.