2027 ICD-10-CM Diagnosis Code Z29.12Encounter for prophylactic antivenin

ICD-10-CM Codes›Z00–Z99›Z20-Z29›Z29

ICD-10-CM Z29.12
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Z29.12 is a billable ICD-10-CM diagnosis code for encounter for prophylactic antivenin. 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 Encounter for prophylactic measures (excludes immunization).

Code Identity

ICD-10-CM Code
Z29.12
Billable Status
Yes — Valid for Submission
Code Describes
Encounter for prophylactic antivenin
Short Description
Encounter for prophylactic antivenin
Same as the full description in the CMS dataset.
Parent Code
Z29.1
Encounter for prophylactic immunotherapy

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ20-Z29Persons with potential health hazards related to communicable diseases
CategoryZ29Encounter for other prophylactic measures
This CodeZ29.12Encounter for prophylactic antivenin

Code EditsBilling

Medicare Code Editor checks that affect claim validity for Z29.12.

Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Present on Admission (POA)Billing

Z29.12 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 communicable diseases (Z20-Z29).

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Z29.12: its own notes plus those printed at Z29 and Chapter 21. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Z29 Encounter for other prophylactic measures applies to 8 codes
  • desensitization to allergens (Z51.6)
  • prophylactic surgery (Z40.-)

Notes

General instructions on how these codes are used.

From Chapter 21 (Z00-Z99) Factors influencing health status and contact with health services applies to 1,425 codes
  • 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.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR FAC005
Encounter for prophylactic measures (excludes immunization)
Default principal diagnosis: inpatient No · outpatient Yes

Convert Z29.12 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
V07.8 Prophyl or tx meas NEC
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement Z29.12 replaces the following previously assigned code(s):

  • Z23 - Encounter for immunization
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Z29.12Overview

What is the ICD-10 code for encounter for prophylactic antivenin?

The ICD-10-CM code for encounter for prophylactic antivenin is Z29.12 (sometimes written as Z2912). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is Z29.12 (Encounter for prophylactic immunotherapy) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report encounter for prophylactic antivenin on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does Z29.12 group to?

On inpatient claims, encounter for prophylactic antivenin 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 Z29.12 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because encounter for prophylactic antivenin describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Is Z29.12 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 encounter for prophylactic antivenin on inpatient claims. The code appears in the Persons with potential health hazards related to communicable diseases (Z20-Z29) range of the CMS exempt list.