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T48.994 ICD-10-CM Code: Poisoning by other agents primarily acting on the respiratory system, undetermined

Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.

Coding at a Glance

7th character: Required — see the character table on this page
Tabular directives: 4 inclusion terms · 1 Excludes1 · 5 Excludes2 · 4 use-additional codes · 7 code-first instructions

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for T48.994 in the official ICD-10-CM tabular list, quoted as published.

Notes without a marker are published on T48.994 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

adverse effect of correct substance properly administered
poisoning by overdose of substance
poisoning by wrong substance given or taken in error
underdosing by (inadvertently) (deliberately) taking less substance than prescribed or instructed

Source: inherited from T36-T50

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

toxic reaction to local anesthesia in pregnancy (O29.3-) Compare T48.994 vs O29.3 →

Source: inherited from T36-T50

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

abuse and dependence of psychoactive substances (F10-F19) Compare T48.994 vs F10 →
abuse of non-dependence-producing substances (F55.-) Compare T48.994 vs F55 →
immunodeficiency due to drugs (D84.821) Compare T48.994 vs D84.821 →
drug reaction and poisoning affecting newborn (P00-P96) Compare T48.994 vs P00 →
pathological drug intoxication (inebriation) (F10-F19) Compare T48.994 vs F10 →

Source: inherited from T36-T50

Code First

Underlying conditions that must be sequenced before this code.

Code first, for adverse effects, the nature of the adverse effect, such as:
adverse effect NOS (T88.7)
aspirin gastritis (K29.-)
blood disorders (D56-D76)
contact dermatitis (L23-L25)
dermatitis due to substances taken internally (L27.-)
nephropathy (N14.0-N14.2)
N14.0-N14.2: N14.0, N14.1, N14.11, N14.19, N14.2

Source: inherited from T36-T50

Use Additional Code

Supplementary codes the tabular list directs you to add.

Use additional code(s) to specify:
manifestations of poisoning
underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
Y63.8-Y63.9: Y63.8, Y63.9
underdosing of medication regimen (Z91.12-, Z91.13-)

Source: inherited from T36-T50

7th Character Guide

"The appropriate 7th character is to be added to each code from category T48"

A — initial encounter
D — subsequent encounter
S — sequela

How the encounter character is assigned. “Initial encounter” means the patient is receiving active treatment for the condition — it is not limited to the first visit, and a different or new provider giving active treatment still assigns it. “Subsequent encounter” covers care during the healing or recovery phase after active treatment. “Sequela” is for complications or conditions that arise as a direct result of the original condition.

ICD-10-CM Official Guidelines for Coding and Reporting, Section I.C.19.a (paraphrased by MedCoder).

Variant codes in this family

T48.994A, T48.994D, T48.994S

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for T48.994

MedCoder structured workflow — derived from this code’s own official record

Before you code T48.994

T48.994 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).
ReviewT48.994A, T48.994D, T48.994S
See the relationships section · Guide: How to choose an ICD-10-CM code →
A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. T48.994 is not valid without one. “Initial” means active treatment, not the first visit (Guidelines I.C.19.a).
See the 7th Character Guide · Guide: 7th characters: initial, subsequent, sequela →
Confirm whether the documentation describes a poisoning, an adverse effect of a correctly prescribed and administered drug, an underdosing, or a toxic effect, and the intent where the record states it: the Table of Drugs and Chemicals separates these by column, and the sequencing differs for each. Poisoning, adverse effect and underdosing guidelines (Guidelines I.C.19.e).
See the Table of Drugs and Chemicals entries · Guide: Poisoning vs adverse effect vs underdosing →
Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with T48.994. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
See the official tabular notes

Choose the right path

Does the documentation support one of the more specific codes beneath T48.994?
Yes → Select that code and continue the checks below on its own page.
No → T48.994 cannot be reported as written; query for the specificity its subcategory needs.
ReviewT48.994A, T48.994D, T48.994S
Does the documentation support a condition named in T48.994’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.
ReviewO29.3
Is the underlying (etiologic) condition the Code First note names documented?
Yes → Sequence the underlying condition first, then T48.994.
No → Continue; do not add an underlying condition the record does not document.
ReviewT88.7, K29, L27
Is the encounter phase documented — active treatment, healing or recovery, or a sequela?
Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
No → The code is invalid without its 7th character — query for the missing element.

Consider T48.994. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement: Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Encounter type: Active treatment, healing or recovery phase, or sequela — the basis of the 7th character (Guidelines I.C.19.a).
The underlying (etiologic) condition: Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).
The conditions the Use Additional Code note names: Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
External cause, place and activity: For the external cause codes reported with the injury or poisoning, where documented (Guidelines I.C.20.a).

Official instructions as workflow

Excludes1 — check before selecting T48.994(1 note)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with T48.994: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
CompareO29.3
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of T48.994(5 notes)
Coding workflow: The conditions named in this note are not included in T48.994. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
CompareF55, D84.821
See the official tabular notes · Guidelines I.A.12.b
Code First — sequencing check(7 notes)
Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before T48.994. Do not add an underlying condition the record does not document.
ReviewT88.7, K29, L27
See the official tabular notes · Guidelines I.A.13
Use Additional Code — after identifying T48.994(4 notes)
Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with T48.994 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.
ReviewY63.6, Z91.12, Z91.13
See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition T48.994 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewO29.3

Documentation: The patient returns during the healing or recovery phase after active treatment of the same condition.

Coding question: Which 7th character applies?

Path: Review the official 7th-character definitions for this family in the 7th Character Guide.

Reason: “Initial encounter” means active treatment, not the first visit; care during recovery takes “subsequent encounter”, and a complication arising from the original condition takes “sequela” (Guidelines I.C.19.a).

Documentation: The underlying condition the Code First note names is documented alongside this condition.

Coding question: How are the two sequenced?

Path: Review the Code First note.

Reason: The underlying condition is sequenced first and the manifestation follows (Guidelines I.A.13).

ReviewT88.7, K29, L27

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Poisoning by other agents primarily acting on the respiratory system, undetermined is a non-billable ICD-10-CM category code (T48.994). A more specific billable subcode must be selected for claims submission.

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Don’t confuse T48.994 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of T48.994 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

O29.3— Excludes1 conflict (Conflict)
Not coded here — these two are mutually exclusive.
Not reported together with this code, except where the two conditions are documented as unrelated.
What moves you there: Documentation of toxic reaction to local anesthesia in pregnancy moves the case to O29.3; the two are not reported together unless documented as unrelated.
Full comparison: T48.994 vs O29.3 →
T48.994A— Encounter relationship (Review)
Same underlying diagnosis, different encounter phase.
The same diagnosis at a different phase of care; one encounter takes one 7th character.
What moves you there: Documentation of a initial encounter moves the case to T48.994A.
Full comparison: T48.994 vs T48.994A →
T48.994D— Encounter relationship (Review)
Same underlying diagnosis, different encounter phase.
The same diagnosis at a different phase of care; one encounter takes one 7th character.
What moves you there: Documentation of a subsequent encounter moves the case to T48.994D.
Full comparison: T48.994 vs T48.994D →
F10— Excludes2 relationship (Informational)
Distinct conditions — both may be reported.
A distinct condition — both may be reported when both are documented.
What moves you there: Documentation of abuse and dependence of psychoactive substances adds F10; it is not part of this code and both may be reported when both are documented.
Full comparison: T48.994 vs F10 →
F19— Excludes2 relationship (Informational)
Distinct conditions — both may be reported.
A distinct condition — both may be reported when both are documented.
What moves you there: Documentation of abuse and dependence of psychoactive substances adds F19; it is not part of this code and both may be reported when both are documented.
Full comparison: T48.994 vs F19 →
F55— Excludes2 relationship (Informational)
Distinct conditions — both may be reported.
A distinct condition — both may be reported when both are documented.
What moves you there: Documentation of abuse of non-dependence-producing substances adds F55; it is not part of this code and both may be reported when both are documented.
Full comparison: T48.994 vs F55 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
Sequencing: 7 Code First instructions — the underlying condition is sequenced before this code when present. See the Code First notes
4 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
5 Excludes2 entries — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

Not billable as written — a more specific code is required: T48.994A, T48.994D, T48.994S.
Requires a 7th character. "The appropriate 7th character is to be added to each code from category T48" Options: T48.994A, T48.994D, T48.994S

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name T48.994 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 11 Excludes2 notes across 2 chapters: T80 — Complications following infusion, transfusion and therapeutic injection (via T48.-), T80-T88 — Complications of surgical and medical care, not elsewhere classified (T80-T88) (via T48.-), T81 — Complications of procedures, not elsewhere classified (via T48.-), T82 — Complications of cardiac and vascular prosthetic devices, implants and grafts (via T48.-), T83 — Complications of genitourinary prosthetic devices, implants and grafts (via T48.-), T84 — Complications of internal orthopedic prosthetic devices, implants and grafts (via T48.-), T85 — Complications of other internal prosthetic devices, implants and grafts (via T48.-), T86 — Complications of transplanted organs and tissue (via T48.-), T87 — Complications peculiar to reattachment and amputation (via T48.-), T88 — Other complications of surgical and medical care, not elsewhere classified (via T48.-), Y63 — Failure in dosage during surgical and medical care (via T48.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 20 Code First instructions across 13 chapters: D64.2 — Secondary sideroblastic anemia due to drugs and toxins (via T48.-), E03.2 — Hypothyroidism due to medicaments and other exogenous substances (via T48.-), E09 — Drug or chemical induced diabetes mellitus (via T48.-), F02 — Dementia in other diseases classified elsewhere (via T48.-), G92.8 — Other toxic encephalopathy (via T48.-), G92.9 — Unspecified toxic encephalopathy (via T48.-), H35.38 — Toxic maculopathy (via T48.-), H91.0 — Ototoxic hearing loss (via T48.-), I42.7 — Cardiomyopathy due to drug and external agent (via T48.-), K22.1 — Ulcer of esophagus (via T48.-), K71 — Toxic liver disease (via T48.-), L53.0 — Toxic erythema (via T48.-), M34.2 — Systemic sclerosis induced by drug and chemical (via T48.-), N14 — Drug- and heavy-metal-induced tubulo-interstitial and tubular conditions (via T48.-), P58.4 — Neonatal jaundice due to drugs or toxins transmitted from mother or given to newborn (via T48.-), Z91.12 — Patient's intentional underdosing of medication regimen (via T48.-), Z91.13 — Patient's unintentional underdosing of medication regimen (via T48.-), Z91.14 — Patient's other noncompliance with medication regimen (via T48.-), Z91.A2 — Caregiver's intentional underdosing of patient's medication regimen (via T48.-), Z91.A3 — Caregiver's unintentional underdosing of patient's medication regimen (via T48.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

Referenced by 99 Use Additional Code instructions across 15 chapters: D46 — Myelodysplastic syndromes (via T48.-), D52.1 — Drug-induced folate deficiency anemia (via T48.-), D59.0 — Drug-induced autoimmune hemolytic anemia (via T48.-), D59.2 — Drug-induced nonautoimmune hemolytic anemia (via T48.-), D59.39 — Other hemolytic-uremic syndrome (via T48.-), D61.1 — Drug-induced aplastic anemia (via T48.-), D64.2 — Secondary sideroblastic anemia due to drugs and toxins (via T48.-), D70.2 — Other drug-induced agranulocytosis (via T48.-), D72.12 — Drug rash with eosinophilia and systemic symptoms syndrome (via T48.-), D84.821 — Immunodeficiency due to drugs (via T48.-), D89.3 — Immune reconstitution syndrome (via T48.-), E03.2 — Hypothyroidism due to medicaments and other exogenous substances (via T48.-), E06.4 — Drug-induced thyroiditis (via T48.-), E09 — Drug or chemical induced diabetes mellitus (via T48.-), E16.0 — Drug-induced hypoglycemia without coma (via T48.-), E22.1 — Hyperprolactinemia (via T48.-), E23.1 — Drug-induced hypopituitarism (via T48.-), E24.2 — Drug-induced Cushing's syndrome (via T48.-), E25.8 — Other adrenogenital disorders (via T48.-), E27.3 — Drug-induced adrenocortical insufficiency (via T48.-), +79 more.

These codes instruct coders to additionally report this code when it applies.

Referenced by 1 Code Also instruction: Z91.1 — Patient's noncompliance with medical treatment and regimen (via T48.-).

These codes suggest coding this condition alongside when both are present.

Contextual Map

Every relationship of T48.994 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run T48.994 with these 24 related codes in Claim Check

Hierarchy

S00-T88 — Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) (S00-T88)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T47-T50 — Hormones & Systemic Agents[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes2 notes (11)

T80 — Complications following infusion, transfusion and therapeutic injection[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T80-T88 — Complications of surgical and medical care, not elsewhere classified (T80-T88)[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T81 — Complications of procedures, not elsewhere classified[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T82 — Complications of cardiac and vascular prosthetic devices, implants and grafts[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T83 — Complications of genitourinary prosthetic devices, implants and grafts[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T84 — Complications of internal orthopedic prosthetic devices, implants and grafts[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T85 — Complications of other internal prosthetic devices, implants and grafts[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
T86 — Complications of transplanted organs and tissue[Excludes2](via T48.-): “poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
and 3 more

Referenced by Code First instructions (20)

D64.2 — Secondary sideroblastic anemia due to drugs and toxins[Code First](via T48.-): “poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
E03.2 — Hypothyroidism due to medicaments and other exogenous substances[Code First](via T48.-): “poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
E09 — Drug or chemical induced diabetes mellitus[Code First](via T48.-): “poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
F02 — Dementia in other diseases classified elsewhere[Code First](via T48.-): “intoxications (T36-T65)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
G92.8 — Other toxic encephalopathy[Code First](via T48.-): “poisoning due to drug or toxin, if applicable, (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
G92.9 — Unspecified toxic encephalopathy[Code First](via T48.-): “poisoning due to drug or toxin, if applicable, (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
H35.38 — Toxic maculopathy[Code First](via T48.-): “poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
H91.0 — Ototoxic hearing loss[Code First](via T48.-): “poisoning due to drug or toxin, if applicable (T36-T65 with fifth or sixth character 1-4)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
and 12 more

Referenced by Use Additional Code instructions (99)

D46 — Myelodysplastic syndromes[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D52.1 — Drug-induced folate deficiency anemia[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D59.0 — Drug-induced autoimmune hemolytic anemia[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D59.2 — Drug-induced nonautoimmune hemolytic anemia[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D59.39 — Other hemolytic-uremic syndrome[Use Additional Code](via T48.-): “code, if applicable, for adverse effect to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D61.1 — Drug-induced aplastic anemia[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D64.2 — Secondary sideroblastic anemia due to drugs and toxins[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
D70.2 — Other drug-induced agranulocytosis[Use Additional Code](via T48.-): “code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
and 91 more

Referenced by Code Also instructions

Z91.1 — Patient's noncompliance with medical treatment and regimen[Code Also](via T48.-): “, if applicable, to identify underdosing of specific drug (T36-T50 with final character 6)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Nearest codes (40)

T48 — Poisoning by, adverse effect of and underdosing of agents primarily acting on smooth and skeletal muscles and the respiratory system[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.903 — Poisoning by unspecified agents primarily acting on the respiratory system, assault[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.903A — Poisoning by unspecified agents primarily acting on the respiratory system, assault, initial encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.903D — Poisoning by unspecified agents primarily acting on the respiratory system, assault, subsequent encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.903S — Poisoning by unspecified agents primarily acting on the respiratory system, assault, sequela[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.904 — Poisoning by unspecified agents primarily acting on the respiratory system, undetermined[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.904A — Poisoning by unspecified agents primarily acting on the respiratory system, undetermined, initial encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
T48.904D — Poisoning by unspecified agents primarily acting on the respiratory system, undetermined, subsequent encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
and 32 more

Change history

FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Common coding questions

Can T48.994 be billed directly?

No. T48.994 (Poisoning by other agents primarily acting on the respiratory system, undetermined) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does T48.994 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category T48.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data: CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Claim edits Official source data: CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data: CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship: Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation: Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Change history

FY2016 — October 1, 2015
In the code set at ICD-10-CM adoption
Poisoning by other agents primarily acting on the respiratory system, undetermined

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to T48.994 in its code family, with their registry titles.

View all codes in the T48 family