2026 ICD-10-CM Diagnosis Code T57.0X2AToxic effect of arsenic and its compounds, intentional self-harm, initial encounter

ICD-10-CM CodesS00–T88T51-T65T57

ICD-10-CM T57.0X2A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T57.0X2A is a billable ICD-10-CM diagnosis code for toxic effect of arsenic and its compounds, intentional self-harm, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 917 through 918. Coders also document this condition as self poisoning caused by arsenic and/or arsenic compound. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under External cause codes: intent of injury, self-harm; External cause codes: poisoning by non-drug; and Suicidal ideation/attempt/intentional self-harm.

Code Identity

ICD-10-CM Code
T57.0X2A
Billable Status
Yes — Valid for Submission
Code Describes
Toxic effect of arsenic and its compounds, intentional self-harm, initial encounter
Short Description
Toxic effect of arsenic and its compounds, self-harm, init
Parent Code
Toxic effect of arsenic and its compounds, intentional self-harm

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT51-T65Toxic effects of substances chiefly nonmedicinal as to source
CategoryT57Toxic effect of other inorganic substances
This CodeT57.0X2AToxic effect of arsenic and its compounds, intentional self-harm, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Self poisoning caused by arsenic and/or arsenic compound

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Toxic effect of other inorganic substances (T57). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

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

CCSR EXT021
External cause codes: intent of injury, self-harm
Default principal diagnosis: inpatient No · outpatient No
CCSR EXT015
External cause codes: poisoning by non-drug
Default principal diagnosis: inpatient No · outpatient No
CCSR MBD012
Suicidal ideation/attempt/intentional self-harm
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INJ023
Toxic effects, initial encounter
Default principal diagnosis: inpatient No · outpatient No

Table of Drugs and ChemicalsClinical

Substances in the Table of Drugs and Chemicals that reference this code family. Always confirm in the Tabular List before coding.

SubstanceAccidentalSelf-harmAssaultUndeter­minedAdverse
Effect
Under­dosing
Arsenate of leadT57.0X1T57.0X2T57.0X3T57.0X4
Arsenate of lead::herbicideT57.0X1T57.0X2T57.0X3T57.0X4
Arsenic, arsenicals (compounds) (dust) (vapor) NECT57.0X1T57.0X2T57.0X3T57.0X4
Arsenic, arsenicals (compounds) (dust) (vapor) NEC::anti-infectivesT57.0X1T57.0X2T57.0X3T57.0X4
Arsenic, arsenicals (compounds) (dust) (vapor) NEC::pesticide (dust) (fumes)T57.0X1T57.0X2T57.0X3T57.0X4
Arsine (gas)T57.0X1T57.0X2T57.0X3T57.0X4
Cacodyl, cacodylic acidT57.0X1T57.0X2T57.0X3T57.0X4
Chlorovinyldichloro-arsine, not in warT57.0X1T57.0X2T57.0X3T57.0X4
DimethylT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::arsine, arsinic acidT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::carbinolT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::carbonateT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::diguanideT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::ketoneT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::ketone::vaporT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::meperidineT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::parathionT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::phthlateT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::polysiloxaneT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::sulfate (fumes)T57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::sulfate (fumes)::liquidT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::sulfoxide (nonmedicinal)T57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::sulfoxide (nonmedicinal)::medicinalT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::tryptamineT57.0X1T57.0X2T57.0X3T57.0X4
Dimethyl::tubocurarineT57.0X1T57.0X2T57.0X3T57.0X4
Diphenylchloroarsine, not in warT57.0X1T57.0X2T57.0X3T57.0X4
Fowler's solutionT57.0X1T57.0X2T57.0X3T57.0X4
Lewisite (gas), not in warT57.0X1T57.0X2T57.0X3T57.0X4
Paris greenT57.0X1T57.0X2T57.0X3T57.0X4
Paris green::insecticideT57.0X1T57.0X2T57.0X3T57.0X4
RealgarT57.0X1T57.0X2T57.0X3T57.0X4
Scheele's greenT57.0X1T57.0X2T57.0X3T57.0X4
Scheele's green::insecticideT57.0X1T57.0X2T57.0X3T57.0X4
Schweinfurth greenT57.0X1T57.0X2T57.0X3T57.0X4
Schweinfurth green::insecticideT57.0X1T57.0X2T57.0X3T57.0X4
Trioxide of arsenicT57.0X1T57.0X2T57.0X3T57.0X4
ViennaT57.0X1T57.0X2T57.0X3T57.0X4
Vienna::greenT57.0X1T57.0X2T57.0X3T57.0X4
Vienna::green::insecticideT57.0X1T57.0X2T57.0X3T57.0X4
Vienna::redT57.0X1T57.0X2T57.0X3T57.0X4
Vienna::red::pharmaceutical dyeT57.0X1T57.0X2T57.0X3T57.0X4
WhiteT57.0X1T57.0X2T57.0X3T57.0X4
White::arsenicT57.0X1T57.0X2T57.0X3T57.0X4
White::helleboreT57.0X1T57.0X2T57.0X3T57.0X4
White::lotion (keratolytic)T57.0X1T57.0X2T57.0X3T57.0X4
White::spiritT57.0X1T57.0X2T57.0X3T57.0X4

Patient EducationClinical

Arsenic

Arsenic is a natural element found in soil and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can get into air, water, and the ground from wind-blown dust. It may also get into water from runoff.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T57.0X2A to ICD-9-CMHistory

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

ICD-9-CM
985.1 Toxic effect arsenic
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
E950.8 Poison-arsenic
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

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 T57.0X2AOverview

Is T57.0X2A a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report toxic effect of arsenic and its compounds, intentional self-harm, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T57.0X2A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for toxic effect of arsenic and its compounds, intentional self-harm, such as an emergency visit or first evaluation.

What MS-DRG does T57.0X2A group to?

When toxic effect of arsenic and its compounds, intentional self-harm, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T57.0X2A?

Under the General Equivalence Mappings, toxic effect of arsenic and its compounds, intentional self-harm, initial encounter converts to ICD-9-CM 985.1 (toxic effect arsenic) and E950.8 (poison-arsenic). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.