Is ICD-10-CM code Z16 billable?

No, Z16 (Resistance to antimicrobial drugs) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code Z16 belong to?

Z16 belongs to Chapter 21 of the ICD-10-CM tabular list: Z00–Z99 (Factors Influencing Health Status and Contact with Health Services).

Z16Not billable, use a more specific code below

Resistance to antimicrobial drugs

chapter 21: Factors Influencing Health Status and Contact with Health Services

19 billable codes under Z16: all are a CC; none map to an HCC.A CC or MCC (major CC) is a secondary diagnosis that raises the MS-DRG payment.

Instructional notes

Excludes1: not coded here, use a different code

Methicillin resistant Staphylococcus aureus infection (A49.02)
Methicillin resistant Staphylococcus aureus pneumonia (J15.212)
Sepsis due to Methicillin resistant Staphylococcus aureus (A41.02)

Code first: code the underlying condition first, then this code

the infection

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Section I.C.1.c Infections resistant to antibiotics (page 22), covers Z16
Identify every infection documented as antibiotic resistant. Add a code from category Z16 after the infection code, but only when the infection code itself does not capture the drug resistance.

All codes under Z16

Z16 can't be used on a claim. Pick a billable code below; grey headings group them.

Z16 MS-DRGs

As the principal diagnosis, all 19 billable codes under Z16 group to MS-DRG 867, 868, or 869 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

Other codes that refer to Z16

Notes on these codes point to Z16.

CH1 Use Additional Code: code to identify resistance to antimicrobial drugs (Z16.-)
J09-J18 Use Additional Code: code, if applicable, to identify resistance to antimicrobial drugs (Z16.-)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Antibiotic Resistance

Antibiotics are medicines that treat bacterial infections in humans and animals. They work by killing the bacteria or making it hard for the bacteria to grow and multiply. When used properly, antibiotics can save lives. But there is a growing problem of antibiotic resistance.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.