2026 ICD-10-CM Diagnosis Code T50.6X3APoisoning by antidotes and chelating agents, assault, initial encounter
T50.6X3A is a billable ICD-10-CM diagnosis code for poisoning by antidotes and chelating agents, assault, 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under External cause codes: intent of injury, assault; External cause codes: poisoning by drug; and Poisoning by drugs, initial encounter.
Code Identity
Code Classification
Coding GuidelinesGuidance
When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of diuretics and other and unspecified drugs, medicaments and biological substances (T50). 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.
Clinical InformationClinical
Cysteamine
a mercaptoethylamine compound that is endogenously derived from the coenzyme a degradative pathway. the fact that cysteamine is readily transported into lysosomes where it reacts with cystine to form cysteine-cysteamine disulfide and cysteine has led to its use in cystine depleting agents for the treatment of cystinosis.Disulfiram
a carbamate derivative used as an alcohol deterrent. it is a relatively nontoxic substance when administered alone, but markedly alters the intermediary metabolism of alcohol. when alcohol is ingested after administration of disulfiram, blood acetaldehyde concentrations are increased, followed by flushing, systemic vasodilation, respiratory difficulties, nausea, hypotension, and other symptoms (acetaldehyde syndrome). it acts by inhibiting aldehyde dehydrogenase.Glutathione
a tripeptide with many roles in cells. it conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.Glutathione Disulfide
a glutathione dimer formed by a disulfide bond between the cysteine sulfhydryl side chains during the course of being oxidized.Glutathione Peroxidase
an enzyme catalyzing the oxidation of 2 moles of glutathione in the presence of hydrogen peroxide to yield oxidized glutathione and water.Glutathione Peroxidase GPX1
one of the most abundant isoenzymes of the glutathione peroxidase family. located in the cytosol and mitochondria, it catalyzes the reduction of hydrogen peroxide to water, functioning to limit the accumulation of hydrogen peroxide and modulating processes that utilize hydrogen peroxide; and also the reduction of other organic hydroperoxides to their corresponding alcohols.Glutathione Reductase
catalyzes the oxidation of glutathione to glutathione disulfide in the presence of nadp+. deficiency in the enzyme is associated with hemolytic anemia. formerly listed as ec 1.6.4.2.Glutathione S-Transferase pi
a glutathione transferase that catalyzes the conjugation of electrophilic substrates to glutathione. this enzyme has been shown to provide cellular protection against redox-mediated damage by free radicals.Glutathione Synthase
one of the enzymes active in the gamma-glutamyl cycle. it catalyzes the synthesis of glutathione from gamma-glutamylcysteine and glycine in the presence of atp with the formation of adp and orthophosphate. ec 6.3.2.3.Glutathione Transferase
a transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic free radicals as well as epoxides and arene oxides to glutathione. addition takes place at the sulfur. it also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.Lactoylglutathione Lyase
an enzyme that catalyzes the interconversion of methylglyoxal and lactate, with glutathione serving as a coenzyme. ec 4.4.1.5.Phospholipid Hydroperoxide Glutathione Peroxidase
a selenoenzyme that converts glutathione plus fatty acid hydroperoxides to glutathione disulfide plus hydroxy fatty acids and water.Protein Disulfide Reductase (Glutathione)
an enzyme that catalyzes the reduction of a protein-disulfide in the presence of glutathione, forming a protein-dithiol. insulin is one of its substrates. ec 1.8.4.2.Obidoxime Chloride
cholinesterase reactivator occurring in two interchangeable isomeric forms, syn and anti.Penicillamine
3-mercapto-d-valine. the most characteristic degradation product of the penicillin antibiotics. it is used as an antirheumatic and as a chelating agent in wilson's disease.
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.
Patient EducationClinical
Poisoning
A poison is any substance that is harmful to your body. You might swallow it, inhale it, inject it, or absorb it through your skin. Any substance can be poisonous if too much is taken. Poisons can include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T50.6X3A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T50.6X3AOverview
Is T50.6X3A (Poisoning by antidotes and chelating agents, assault) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by antidotes and chelating agents, assault, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T50.6X3A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for poisoning by antidotes and chelating agents, assault, such as an emergency visit or first evaluation.
What MS-DRG does T50.6X3A group to?
When poisoning by antidotes and chelating agents, assault, 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 T50.6X3A?
Under the General Equivalence Mappings, poisoning by antidotes and chelating agents, assault, initial encounter converts to ICD-9-CM 977.2 (poisoning-antidotes NEC) and E962.0 (assault-pois w medic agt). 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.
