Z79.818 Long term (current) use of other agents affecting estrogen receptors and estrogen levels

The ICD-10-CM code for Long term (current) use of other agents affecting estrogen receptors and estrogen levels is Z79.818 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

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

Section

Z77-Z99: Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99)

Category Z79

41 codes (32 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to Z79.818:

• Long-term (current) (prophylactic) drug therapy (use of) › estrogen receptor downregulators
• Long-term (current) (prophylactic) drug therapy (use of) › megestrol acetate (Megace)
• Long-term (current) (prophylactic) drug therapy (use of) › goserelin acetate (Zoladex)
• Long-term (current) (prophylactic) drug therapy (use of) › agents affecting estrogen receptors and estrogen levels NEC
• Long-term (current) (prophylactic) drug therapy (use of) › fulvestrant (Faslodex)
• Long-term (current) (prophylactic) drug therapy (use of) › leuprolide acetate (leuprorelin) (Lupron)
• Long-term (current) (prophylactic) drug therapy (use of) › gonadotropin-releasing hormone (GnRH) agonist
• Therapy › drug, long-term (current) (prophylactic) › agents affecting estrogen receptors and estrogen levels NEC

Inclusion Terms

• Long term (current) use of estrogen receptor downregulators
• Long term (current) use of fulvestrant (Faslodex)
• Long term (current) use of gonadotropin-releasing hormone (GnRH) agonist
• Long term (current) use of goserelin acetate (Zoladex)
• Long term (current) use of leuprolide acetate (leuprorelin) (Lupron)
• Long term (current) use of megestrol acetate (Megace)

U.S. Hospital Utilization

• An estimated 11,040 U.S. inpatient stays in 2023 included Z79.818 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)