Skip to main content

T46.1 vs T46.5X3D

T46.1 (Poisoning by, adverse effect of and underdosing of calcium-channel blockers) compared with T46.5X3D (Poisoning by other antihypertensive drugs, assault, subsequent encounter), from the official CMS tabular data.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Summary

These codes can be reported together when both conditions are documented, because T46.5X3D lists T46.1 under Excludes2, which marks them as distinct conditions.

Official rule
What is different?

Title wording and billing status.The titles share “Poisoning by”; T46.1 says “adverse effect of and underdosing of calcium-channel blockers” where T46.5X3D says “other antihypertensive drugs, assault, subsequent encounter”. T46.1 is a non-billable header; T46.5X3D is billable.

Registry fact

Can these codes be reported together?

Yes, when both are documented.T46.5X3D lists T46.1 under Excludes2: “poisoning by, adverse effect of and underdosing of calcium-channel blockers (T46.1)”. Excludes2 marks distinct conditions that may both be reported when both are documented.

Official ruleGuide: Excludes1 vs Excludes2

Is there an Excludes2 relationship?

Yes.T46.5X3D’s tabular entry: “poisoning by, adverse effect of and underdosing of calcium-channel blockers (T46.1)”. The note covers T46.1.

Official ruleGuide: Excludes1 vs Excludes2

Is one a parent or header code?

One is a header.T46.1 is a non-billable header, but T46.5X3D is not one of its subdivisions.

Registry fact

Nothing found in 4 other checks
Is there an Excludes1 relationship?

None.Neither entry carries an Excludes1 note that names the other code. T46.1 carries 2 Excludes1 notes and T46.5X3D carries 2 Excludes1 notes covering other codes; the side-by-side table quotes them.

Official rule

Is one more specific?

No.Neither is a subdivision of the other, and neither title is the unspecified form; they describe different conditions within category T46.

Registry fact

Are there sequencing instructions?

None.Neither entry carries a Code First or Use Additional Code note that names the other.

Official rule

Are there other coding relationships?

None found.No laterality, encounter-phase, Table of Neoplasms, Table of Drugs and Chemicals, or history-versus-active-disease relationship links these codes.

MedCoder-derived

Official rule: a tabular instructional note or a section of the ICD-10-CM Official Guidelines, quoted as published. Registry fact: the codes’ own published attributes (titles, billable status, position in the hierarchy, code set). MedCoder-derived: a reading MedCoder computes from those facts; it is not itself a rule. How to read the labels

Can these codes be reported together?

Informational

Excludes2 relationship

T46.5X3D
Poisoning by other antihypertensive drugs, assault, subsequent encounter
↔
T46.1
Poisoning by, adverse effect of and underdosing of calcium-channel blockers

What we found

Yes, when both are documented.T46.5X3D carries an Excludes2 note covering T46.1: “poisoning by, adverse effect of and underdosing of calcium-channel blockers (T46.1)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

What to review

Report both only when the documentation supports both conditions; otherwise report the one documented.

Guide: Excludes1 vs Excludes2Check these on a claim

Why it matters

An Excludes2 note means the excluded condition is not part of the code above it, but a patient can have both. Report both when both are documented.

Source / rule

CMS ICD-10-CM tabular instructional notes

Official guidance behind these answers

  • Section I.A.12.b — Excludes2 · applies to: Excludes2

    A type 2 Excludes note represents “Not included here.” An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

    ICD-10-CM Official Guidelines FY2027

Quoted from the ICD-10-CM Official Guidelines for Coding and Reporting in effect for the release shown. The tabular notes above are the code-level instruction; these sections are the convention that says how such a note is applied. Source document (CMS PDF) · Release and checksum

Side by side

Similar descriptions do not make codes interchangeable. The documentation and the official instructions decide which code applies.

Official descriptionDiffers
T46.1

Poisoning by, adverse effect of and underdosing of calcium-channel blockers

T46.5X3D

Poisoning by other antihypertensive drugs, assault, subsequent encounter

StatusDiffers
T46.1
Non-billable header

A header is not reported on a claim; a code beneath it is.

Report instead: T46.1X1A, T46.1X1D, T46.1X1S, T46.1X2A, T46.1X2D

T46.5X3D
Billable
Excludes1Same for both
  • poisoning by, adverse effect of and underdosing of metaraminol (T44.4)
  • toxic reaction to local anesthesia in pregnancy (O29.3-)
Excludes2Differs
Only at T46.1

No note of its own beyond the shared notes

Only at T46.5X3D
  • poisoning by, adverse effect of and underdosing of beta-adrenoreceptor antagonists (T44.7)
  • poisoning by, adverse effect of and underdosing of calcium-channel blockers (T46.1)
  • poisoning by, adverse effect of and underdosing of diuretics (T50.0-T50.2)
Shared by both codes (5 notes)
  • abuse and dependence of psychoactive substances (F10-F19)
  • abuse of non-dependence-producing substances (F55.-)
  • immunodeficiency due to drugs (D84.821)
  • drug reaction and poisoning affecting newborn (P00-P96)
  • pathological drug intoxication (inebriation) (F10-F19)
Code firstSame for both
  • , 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)
Use additional codeSame for both
  • code(s) to specify:
  • manifestations of poisoning
  • underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
  • underdosing of medication regimen (Z91.12-, Z91.13-)
CategorySame for both

T46 Poisoning by, adverse effect of and underdosing of agents primarily affecting the cardiovascular system

ChapterSame for both

S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)

IncludesSame for both
  • 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
7th characterSame for both
  • The appropriate 7th character is to be added to each code from category T46

No Code also note at either code.

Notes are the code’s own tabular entry, quoted as published. A note that names the other code is the one the verdict above rests on. In a row that differs, each code’s own notes are listed under it, and the notes every code shares are listed once beneath them.

Edit this comparisonCheck a whole claim

Derived from the official CMS ICD-10-CM tabular data (FY2027). A coding-rule comparison, not billing advice: payer-specific edits and medical-necessity policy are outside its scope. All data sources