2027 ICD-10-CM Diagnosis Code Z91.018Allergy to other foods
Z91.018 is a billable ICD-10-CM diagnosis code for allergy to other foods. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 951. The code is not accepted as a principal diagnosis by the Medicare Code Editor and exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified status.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for Z91.018.
Present on Admission (POA)Billing
Z91.018 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Allergy to almond
- Allergy to almond oil
- Allergy to apple
- Allergy to Arachis oil
- Allergy to banana
- Allergy to barley
- Allergy to bean
- Allergy to caffeine
- Allergy to carrot
- Allergy to cashew nut
- Allergy to celery
- Allergy to cherry
- Allergy to chicken meat
- Allergy to chocolate
- Allergy to cinnamon
- Allergy to citrus fruit
- Allergy to coconut oil
- Allergy to corn
- Allergy to dietary mushroom
- Allergy to fenugreek
- Allergy to food additive
- Allergy to fruit
- Allergy to gelatin
- Allergy to gluten
- Allergy to grain
- Allergy to hazelnut
- Allergy to kiwi fruit
- Allergy to lupine seed
- Allergy to macadamia nut
- Allergy to mango fruit
- Allergy to meat
- Allergy to mustard seasoning
- Allergy to nut
- Allergy to oat
- Allergy to olive oil
- Allergy to pea
- Allergy to phosphodiesterase inhibitor
- Allergy to pineapple
- Allergy to poppy seed
- Allergy to potato
- Allergy to pulse vegetable
- Allergy to rye
- Allergy to seed
- Allergy to soy protein
- Allergy to strawberry
- Allergy to tomato
- Allergy to tree nut
- Allergy to vegetable
- Allergy to walnut
- Allergy to watermelon
- Allergy to wheat
- Gastrointestinal hypersensitivity caused by food
- History of food allergy
- History of food hypersensitivity
- Pollen-food allergy
- Propensity to adverse reactions to food
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to Z91.018: its own notes plus those printed at Z91.01, Z91.0, Z91, block Z77-Z99, and Chapter 21. A note printed at a category, block or chapter applies to every code under it.
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Allergy to nuts other than peanuts
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- Allergy status to drugs, medicaments, and biological substances (Z88.-)
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
Notes
General instructions on how these codes are used.
- Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
- (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
- (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name Z91.018, its category, or a range that includes it.
Excludes2 1
These codes carry an Excludes2 note naming Z91.018: its condition is not part of those codes, and both may be reported when the patient has both.
Use Additional Code 2
These codes say to use an additional code from the note, and Z91.018 is one of the codes named.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Allergy, allergic (reaction) (to) T78.40
food (any) (ingested) NEC T78.19
status (without reaction) Z91.018
specified NEC Z91.018
personal (of) See Also: History, family (of);
food Z91.018
specified food NEC Z91.018
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Food Allergy
A food allergy is an abnormal immune system reaction to certain foods. Your immune system normally protects you from germs. But if you have a food allergy, your immune system mistakenly reacts to certain foods as if they were harmful. This reaction is usually mild. But in some cases, it can be serious or even life-threatening.
The full article covers:
- What is a food allergy?
- Who is more likely to develop a food allergy?
- What are the symptoms of food allergies?
- How are food allergies diagnosed?
- What are the treatments for food allergies?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert Z91.018 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About Z91.018Overview
What is the ICD-10 code for allergy to other foods?
The ICD-10-CM code for allergy to other foods is Z91.018 (sometimes written as Z91018). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is Z91.018 (Food allergy status) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report allergy to other foods on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does Z91.018 group to?
On inpatient claims, allergy to other foods maps to MS-DRG 951 (other Factors Influencing Health Status), which carries a relative weight of 0.5574. Higher weights mean higher Medicare reimbursement.
Can Z91.018 be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because allergy to other foods describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.
Is Z91.018 exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for allergy to other foods on inpatient claims. The code appears in the Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99) range of the CMS exempt list.
