ICD-10-CM Code Z91.09

Other allergy status, other than to drugs and biological substances

Version 2020 Billable Code Unacceptable Principal Diagnosis POA Exempt

Valid for Submission

Z91.09 is a billable code used to specify a medical diagnosis of other allergy status, other than to drugs and biological substances. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code Z91.09 might also be used to specify conditions or terms like allergy to aluminum, allergy to animal dander, allergy to animal protein, allergy to biocide, allergy to citric acid, allergy to cosmetic material, etc The code is exempt from present on admission (POA) reporting for inpatient admissions to general acute care hospitals.

The code Z91.09 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.

Short Description:Oth allergy status, oth than to drugs and biolg substances
Long Description:Other allergy status, other than to drugs and biological substances

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code Z91.09 are found in the index:

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10 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.


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

  • Allergy to aluminum
  • Allergy to animal dander
  • Allergy to animal protein
  • Allergy to biocide
  • Allergy to citric acid
  • Allergy to cosmetic material
  • Allergy to cow dander
  • Allergy to Dermatophagoides farinae protein
  • Allergy to Dermatophagoides pteronyssinus protein
  • Allergy to dimethicone
  • Allergy to dust
  • Allergy to dust mite protein
  • Allergy to dust mite protein
  • Allergy to emollient
  • Allergy to feathers
  • Allergy to fungus
  • Allergy to fungus
  • Allergy to guinea pig dander
  • Allergy to horse dander
  • Allergy to laboratory animal dander
  • Allergy to metal
  • Allergy to mineral oil
  • Allergy to mugwort pollen
  • Allergy to paraffin
  • Allergy to perfume
  • Allergy to plant fiber
  • Allergy to pollen
  • Allergy to pollen
  • Allergy to pyrethroid
  • Allergy to rubber
  • Allergy to rust protein
  • Allergy to silicone
  • Allergy to terpene
  • Allergy to tree resin
  • Allergy to wall pellitory pollen
  • Allergy to weed pollen
  • Allergy to white paraffin
  • Allergy to wood dust
  • Allergy to wool
  • Allergy to wool alcohol
  • Allergy to yeast antigen
  • Allergy to yellow paraffin
  • Diffuse dermatitis
  • H/O: non-drug allergy
  • Severe dermatitis, multiple allergies, metabolic wasting syndrome

Present on Admission (POA)

Z91.09 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 Indicator CodePOA Reason 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 Z91.09 to ICD-9

  • V15.09 - Hx-allergy NEC (Approximate Flag)

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)

Code History

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

Information for Patients


An allergy is a reaction by your immune system to something that does not bother most other people. People who have allergies often are sensitive to more than one thing. Substances that often cause reactions are

  • Pollen
  • Dust mites
  • Mold spores
  • Pet dander
  • Food
  • Insect stings
  • Medicines

Normally, your immune system fights germs. It is your body's defense system. In most allergic reactions, however, it is responding to a false alarm. Genes and the environment probably both play a role.

Allergies can cause a variety of symptoms such as a runny nose, sneezing, itching, rashes, swelling, or asthma. Allergies can range from minor to severe. Anaphylaxis is a severe reaction that can be life-threatening. Doctors use skin and blood tests to diagnose allergies. Treatments include medicines, allergy shots, and avoiding the substances that cause the reactions.

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