2027 ICD-10-CM Diagnosis Code Z03.6Encounter for observation for suspected toxic effect from ingested substance ruled out
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 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 951. 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
Code Classification
Present on Admission (POA)Billing
Z03.6 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Persons encountering health services for examinations (Z00-Z13).
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to Z03.6: its own notes plus those printed at Z03, block Z00-Z13, and Chapter 21. A note printed at a category, block or chapter applies to every code under it.
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Encounter for observation for suspected adverse effect from drug
- Encounter for observation for suspected poisoning
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Notes
General instructions on how these codes are used.
- 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.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name Z03.6, its category, or a range that includes it.
Excludes1 2
These codes carry an Excludes1 note naming Z03.6: they are not reported together with it, unless the two conditions are unrelated.
- Z01 Encounter for other special examination without complaint, suspected or reported diagnosisencounter for examination for suspected conditions, proven not to exist (Z03.-) names Z03.-, which includes this code
- Z71.1 Person with feared health complaint in whom no diagnosis is mademedical observation for suspected diseases and conditions proven not to exist (Z03.-) names Z03.-, which includes this code
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Observation (following) (for) (without need for further medical care) Z04.9
adverse effect of drug Z03.6
suicide attempt, alleged NEC Z03.89
self-poisoning Z03.6
suspected, ruled out See Also: Suspected condition, ruled out;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Convert Z03.6 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
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, 2026 through September 30, 2027.
What MS-DRG does Z03.6 group to?
When encounter for observation for suspected toxic effect from ingested substance ruled out is the principal diagnosis on an inpatient stay, it groups to MS-DRG 951 (other Factors Influencing Health Status), which carries a relative weight of 0.5574. Higher weights mean higher Medicare reimbursement.
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. The code appears in the Persons encountering health services for examinations (Z00-Z13) range of the CMS exempt list.
Can Z03.6 be reported with a code from Z77?
Not as a rule. The Excludes1 note at Z03, which applies to Z03.6, lists "contact with and (suspected) exposures hazardous to health (Z77.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
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.
