Z28.01 Immunization not carried out because of acute illness of patient

The ICD-10-CM code for Immunization not carried out because of acute illness of patient is Z28.01 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

21: Factors influencing health status and contact with health services (Z00-Z99)

Section

Z20-Z29: Persons with potential health hazards related to communicable diseases (Z20-Z29)

Category Z28

23 codes (17 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to Z28.01:

• Immunization › not done (not carried out) › because (of) › acute illness of patient

U.S. Hospital Utilization

• An estimated 345 U.S. inpatient stays in 2023 included Z28.01 among the documented diagnoses.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Used with any code in range A00.0-T88.9, Z00-Z99

1) Used with any code in the range of A00.0-T88.9, Z00-Z99 An external cause code may be used with any code in the range of A00.0-T88.9, Z00-Z99, classification that represents a health condition due to an external cause. Though they are most applicable to injuries, they are also valid for use with such things as infections or diseases due to an external source, and other health conditions, such as a heart attack that occurs during strenuous physical activity.

Additional codes with observation code (fragment)

observation code, but only if they are unrelated to the suspected condition being observed.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)