Is Z91.0120 a billable ICD-10-CM code?

Yes. Z91.0120 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does Z91.0120 sit in the tabular list?

Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).

Z91.0120

Z91.0120 — Allergy to eggs, unspecified

Billable / specific codeICD-10-CMPOA exempt

Z91.0120 is a billable, specific ICD-10-CM code for allergy to eggs, unspecified. It is valid for submission on a claim.

Excludes2 inherited from the categories above Z91.0120

Also inherited, and the opposite of Excludes1: these conditions are not part of Z91.0120, but a patient can have both, so you may code both.

Written on Z91.01 — Food allergy status

food additives allergy status (Z91.02)

Written on Z91.0 — Allergy status, other than to drugs and biological substances

Allergy status to drugs, medicaments, and biological substances (Z88.-)

Written on Z91 — Personal risk factors, not elsewhere classified

contact with and (suspected) exposures hazardous to health (Z77.-)
exposure to pollution and other problems related to physical environment (Z77.1-)
female genital mutilation status (N90.81-)
occupational exposure to risk factors (Z57.-)
personal history of physical injury and trauma (Z87.81, Z87.82-)

Risk adjustment

Z91.0120 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

Z91.0120 is named in 16 Medicare coverage policies — 16 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A57043Billing and Coding: RAST Type Tests
A57181Billing and Coding: Allergy Testing
A57473Billing and Coding: Allergy Testing
A57473Billing and Coding: Allergy Testing

How Z91.0120 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to Z91.0120.

Allergy, allergic›food NEC›status›eggs
History›personal›allergy›food›eggs

Code history

What changed, and when. Derived by diffing consecutive CMS release files — which matters when you are defending a code assigned under an earlier edition.

addedFY2024-FY2026
Allergy to eggs, unspecified

Related codes at this level

Codes that share Z91.012. If Z91.0120 is not quite right, the correct code is usually one of these.

Questions about Z91.0120

Is Z91.0120 a billable ICD-10-CM code?: Yes. Z91.0120 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does Z91.0120 sit in the tabular list?: Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).