2026 ICD-10-CM Diagnosis Code Z03.6Encounter for observation for suspected toxic effect from ingested substance ruled out

ICD-10-CM Codes›Z00–Z99›Z00-Z13›Z03

ICD-10-CM Z03.6
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Z03.6 is a billable ICD-10-CM diagnosis code for encounter for observation for suspected toxic effect from ingested substance ruled out. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Encounter for observation and examination for conditions ruled out (excludes infectious disease, neoplasm, mental disorders).

Code Identity

ICD-10-CM Code
Z03.6
Billable Status
Yes — Valid for Submission
Code Describes
Encounter for observation for suspected toxic effect from ingested substance ruled out
Short Description
Encntr for obs for susp toxic eff from ingest sub ruled out
Parent Code
Z03
Encounter for medical observation for suspected diseases and conditions ruled out

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ00-Z13Persons encountering health services for examinations
CategoryZ03Encounter for medical observation for suspected diseases and conditions ruled out
This CodeZ03.6Encounter for observation for suspected toxic effect from ingested substance ruled out

Present on Admission (POA)Billing

Z03.6 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Encounter for observation for suspected adverse effect from drug
  • Encounter for observation for suspected poisoning

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Observation(following) (for) (without need for further medical care)
      • adverse effect of drug
    • Observation(following) (for) (without need for further medical care)
      • suicide attempt, alleged NEC
        • self-poisoning
    • Observation(following) (for) (without need for further medical care)
      • suspected, ruled out
        • drug poisoning or adverse effect
    • Observation(following) (for) (without need for further medical care)
      • suspected, ruled out
        • suicide attempt, alleged
          • self-poisoning
    • Observation(following) (for) (without need for further medical care)
      • suspected, ruled out
        • toxic effects from ingested substance (drug) (poison)
    • Observation(following) (for) (without need for further medical care)
      • toxic effects from ingested substance (drug) (poison)
    • Self-poisoning
      • observation following (alleged) attempt

Clinical ClassificationClinical

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

CCSR FAC003
Encounter for observation and examination for conditions ruled out (excludes infectious disease, neoplasm, mental disorders)
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert Z03.6 to ICD-9-CMHistory

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

ICD-9-CM
V71.89 Observ-suspect cond NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Z03.6Overview

Is Z03.6 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report encounter for observation for suspected toxic effect from ingested substance ruled out on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is Z03.6 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 observation for suspected toxic effect from ingested substance ruled out on inpatient claims.

What is the ICD-9 equivalent of Z03.6?

Under the General Equivalence Mappings, encounter for observation for suspected toxic effect from ingested substance ruled out converts to ICD-9-CM V71.89 (observ-suspect cond NEC). The mapping is approximate, so confirm the match fits the documentation.