2025 ICD-10-CM Diagnosis Code Z88.9
Allergy status to unspecified drugs, medicaments and biological substances
- ICD-10-CM Code:
- Z88.9
- ICD-10 Code for:
- Allergy status to unspecified drug/meds/biol subst
- Is Billable?
- Yes - Valid for Submission
- Code Navigator:
Z88.9 is a billable diagnosis code used to specify a medical diagnosis of allergy status to unspecified drugs, medicaments and biological substances. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2024 through September 30, 2025. 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.
Unspecified diagnosis codes like Z88.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.
Approximate Synonyms
The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.
- Allergy to drug
- Atopy
- Cross sensitivity reaction
- H/O: biological substance allergy
- H/O: multiple allergies
- History of anaphylaxis
- History of atopy
- History of drug-induced anaphylaxis
- Hypersensitivity to endogenous antigen
- Hypersensitivity to foreign antigen
- Non-immunoglobulin E-mediated drug sensitivity
- Propensity to adverse reactions to drug
Clinical Classification
Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.
They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.
Other specified status
CCSR Code: FAC025
Inpatient Default: X - Not applicable.
Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.
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).
- - History
- - personal (of) - See Also: History, family (of);
- - allergy (to) - Z88.9
- - drugs, medicaments and biological substances - Z88.9
- - medicinal agents - Z88.9
- - allergy (to) - Z88.9
- - personal (of) - See Also: History, family (of);
Code Edits
The Medicare Code Editor (MCE) detects errors and inconsistencies in ICD-10-CM diagnosis coding that can affect Medicare claim validity. These Medicare code edits help medical coders and billing professionals determine when a diagnosis code is not appropriate as a principal diagnosis, does not meet coverage criteria. Use this list to verify whether a code is valid for Medicare billing and to avoid claim rejections or denials due to diagnosis coding issues.
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)
Z88.9 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: Y
Reason: Diagnosis was present at time of inpatient admission.
CMS Pays CC/MCC DRG? YES
POA Indicator: N
Reason: Diagnosis was not present at time of inpatient admission.
CMS Pays CC/MCC DRG? NO
POA Indicator: U
Reason: Documentation insufficient to determine if the condition was present at the time of inpatient admission.
CMS Pays CC/MCC DRG? NO
POA Indicator: W
Reason: Clinically undetermined - unable to clinically determine whether the condition was present at the time of inpatient admission.
CMS Pays CC/MCC DRG? YES
POA Indicator: 1
Reason: Unreported/Not used - Exempt from POA reporting.
CMS Pays CC/MCC DRG? NO
Convert Z88.9 to ICD-9-CM
Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.
Hx-drug allergy NOS
ICD-9-CM: V14.9
This is a direct match with no additional mapping qualifiers. The absence of a flag generally means the mapping is considered exact or precise. In other words, the ICD-10 code maps cleanly to the ICD-9 code without qualification, approximation, or needing multiple codes.
Patient Education
Drug Reactions
Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.
What is a drug interaction?
A drug interaction is a change in the way a drug acts in the body when taken with certain other drugs, foods, or supplements or when taken while you have certain medical conditions. Examples include:
- Two drugs, such as aspirin and blood thinners
- Drugs and food, such as statins and grapefruit
- Drugs and supplements, such as gingko and blood thinners
- Drugs and medical conditions, such as aspirin and peptic ulcers
Interactions could cause a drug to be more or less effective, cause side effects, or change the way one or both drugs work.
What are side effects?
Side effects are unwanted, usually unpleasant, effects caused by medicines. Most are mild, such as a stomachache, dry mouth, or drowsiness, and go away after you stop taking the medicine. Others can be more serious. Sometimes a drug can interact with a disease that you have and cause a side effect. For example, if you have a heart condition, certain decongestants can cause you to have a rapid heartbeat.
What are drug allergies?
Drug allergies are another type of reaction. They can range from mild to life-threatening. Skin reactions, such as hives and rashes, are the most common type. Anaphylaxis, a serious allergic reaction, is less common.
How can I stay safe when taking medicines?
When you start a new prescription or over-the-counter medicine, make sure you understand how to take it correctly. Know which other medicines, foods, and supplements you need to avoid. Always talk to your health care provider or pharmacist if you have questions about your medicines.
[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 - Code Updated, effective from 10/1/2020 through 9/30/2021
- New Description: Allergy status to unspecified drugs, medicaments and biological substances
- Previous Description: Allergy status to unspecified drugs, medicaments and biological substances
- 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.
