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T61.77 ICD-10-CM Code: Other fish poisoning

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

7th character
Required — see the character table on this page
Tabular directives
14 Excludes1 · 4 use-additional codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for T61.77 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on T61.77 itself; “inherited from” names the category or block whose note applies here.

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).

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code(s):
  • for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70)
  • personal history of foreign body fully removed (Z87.821)
  • to identify any retained foreign body, if applicable (Z18.-)

Source: inherited from T51-T65

7th Character Guide

"The appropriate 7th character is to be added to each code from category T61"

  • 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

T61.771A, T61.771D, T61.771S, T61.772A, T61.772D, T61.772S, T61.773A, T61.773D

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 T61.77

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

Before you code T61.77

  1. T61.77 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).

    ReviewT61.771, T61.772, T61.773, T61.774

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. “Other” (NEC) means the condition is specified in the record but no dedicated code captures it. Confirm the documented form is not one a sibling code names before settling on T61.77; if the record states no specifics at all, the unspecified sibling applies instead. “Other” codes are for documented conditions the classification gives no specific code; “unspecified” codes are for records lacking the detail (Guidelines I.A.9.a, I.A.9.b).

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  3. A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. T61.77 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 →

  4. 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 →

  5. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with T61.77. 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

  1. Does the documentation support one of the more specific codes beneath T61.77?
    Yes → Select that code and continue the checks below on its own page.
    No → T61.77 cannot be reported as written; query for the specificity its subcategory needs.

    ReviewT61.771, T61.772, T61.773, T61.774

  2. Does the documentation support a condition named in T61.77’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.

    ReviewT78.0, A05, L23.6, L25.4, L27.2, K52.21

  3. 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 T61.77. 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 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).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting T61.77(14 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with T61.77: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareT78.0, A05, L23.6, L25.4, L27.2, K52.21

    See the official tabular notes · Guidelines I.A.12.a

  • Use Additional Code — after identifying T61.77(4 notes)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with T61.77 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    ReviewZ87.821, Z18

    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 T61.77 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).

ReviewT78.0, A05, L23.6, L25.4, L27.2, K52.21

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: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with T61.77?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

ReviewZ87.821, Z18

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.

Coding context

The comparisons, hierarchy, index entries, guidelines, relationships, risk-adjustment and coverage context a coder commonly needs. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Don’t confuse T61.77 with…

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

The codes most likely to be picked instead of T61.77 — 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.

  • T78.0— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of anaphylactic reaction or shock due to adverse food reaction moves the case to T78.0; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs T78.0 →

  • A05— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of bacterial foodborne intoxications moves the case to A05; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs A05 →

  • L23.6— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of dermatitis moves the case to L23.6; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs L23.6 →

  • L25.4— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of dermatitis moves the case to L25.4; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs L25.4 →

  • L27.2— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of dermatitis moves the case to L27.2; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs L27.2 →

  • K52.21— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of food protein-induced enterocolitis syndrome moves the case to K52.21; the two are not reported together unless documented as unrelated.

    Full comparison: T61.77 vs K52.21 →

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.

Code Overview

Other fish poisoning is a non-billable ICD-10-CM category code (T61.77). 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.

Decision Points

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

  1. 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
  2. 4 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
  3. 14 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 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

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 T61.77 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 1 Excludes1 note: A05 — Other bacterial foodborne intoxications, not elsewhere classified (via T61.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 13 Excludes2 notes across 2 chapters: T63 — Toxic effect of contact with venomous animals and plants (via T61.-), T63.5 — Toxic effect of contact with venomous fish (via T61.-), T80 — Complications following infusion, transfusion and therapeutic injection (via T61.-), T80-T88 — Complications of surgical and medical care, not elsewhere classified (T80-T88) (via T61.-), T81 — Complications of procedures, not elsewhere classified (via T61.-), T82 — Complications of cardiac and vascular prosthetic devices, implants and grafts (via T61.-), T83 — Complications of genitourinary prosthetic devices, implants and grafts (via T61.-), T84 — Complications of internal orthopedic prosthetic devices, implants and grafts (via T61.-), T85 — Complications of other internal prosthetic devices, implants and grafts (via T61.-), T86 — Complications of transplanted organs and tissue (via T61.-), T87 — Complications peculiar to reattachment and amputation (via T61.-), T88 — Other complications of surgical and medical care, not elsewhere classified (via T61.-), Z77 — Other contact with and (suspected) exposures hazardous to health (via T61.-).

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

Referenced by 68 Code First instructions across 14 chapters: D61.2 — Aplastic anemia due to other external agents (via T61.-), D64.2 — Secondary sideroblastic anemia due to drugs and toxins (via T61.-), E03.2 — Hypothyroidism due to medicaments and other exogenous substances (via T61.-), E09 — Drug or chemical induced diabetes mellitus (via T61.-), F02 — Dementia in other diseases classified elsewhere (via T61.-), G21.2 — Secondary parkinsonism due to other external agents (via T61.-), G62.2 — Polyneuropathy due to other toxic agents (via T61.-), G70.1 — Toxic myoneural disorders (via T61.-), G72.2 — Myopathy due to other toxic agents (via T61.-), G92.8 — Other toxic encephalopathy (via T61.-), G92.9 — Unspecified toxic encephalopathy (via T61.-), H10.21 — Acute toxic conjunctivitis (via T61.-), H35.38 — Toxic maculopathy (via T61.-), H46.3 — Toxic optic neuropathy (via T61.-), H91.0 — Ototoxic hearing loss (via T61.-), I42.7 — Cardiomyopathy due to drug and external agent (via T61.-), J68 — Respiratory conditions due to inhalation of chemicals, gases, fumes and vapors (via T61.-), J69.1 — Pneumonitis due to inhalation of oils and essences (via T61.-), J69.8 — Pneumonitis due to inhalation of other solids and liquids (via T61.-), J70.8 — Respiratory conditions due to other specified external agents (via T61.-), +48 more.

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.

Related Codes

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Poisoning”; these codes share that main term but sit in a different category of the Tabular List.

A02.0 — Salmonella enteritis (food NEC, due to, salmonella, with, gastroenteritis), A02.1 — Salmonella sepsis (food NEC, due to, salmonella, with, sepsis), A02.9 — Salmonella infection, unspecified (Bacillus B), A05.0 — Foodborne staphylococcal intoxication (Staphylococcus, food), A05.1 — Botulism food poisoning (botulism), A05.2 — Foodborne Clostridium perfringens [Clostridium welchii] intoxication (food NEC, due to, Clostridium), A05.3 — Foodborne Vibrio parahaemolyticus intoxication (food NEC, due to, Vibrio, parahaemolyticus), A05.5 — Foodborne Vibrio vulnificus intoxication (food NEC, due to, Vibrio, vulnificus), A05.9 — Bacterial foodborne intoxication, unspecified (food NEC), D55.0 — Anemia due to glucose-6-phosphate dehydrogenase [G6PD] deficiency (fava bean), E87.79 — Other fluid overload (water), J70.0 — Acute pulmonary manifestations due to radiation (radiation), T56.0 — Toxic effects of lead and its compounds (lead), T62.9 — Toxic effect of unspecified noxious substance eaten as food (food NEC, noxious or naturally toxic), T65.2 — Toxic effect of tobacco and nicotine (tobacco), T65.81 — Toxic effect of latex (latex), T65.82 — Toxic effect of harmful algae and algae toxins (algae and toxins), T65.891 — Toxic effect of other specified substances, accidental (unintentional) (specified substance NEC)

Contextual Map

Every relationship of T61.77 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 T61.77 with these 17 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Excludes2 notes (13)

Referenced by Code First instructions (68)

Nearest codes (40)

Change history

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

Deep reference

Published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Can T61.77 be billed directly?

No. T61.77 (Other fish poisoning) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does T61.77 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category T61.

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 FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 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.

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 20, 2026 · All releases and sources

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

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "T61.77 — Other fish poisoning." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/t61.77-other-fish-poisoning

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Other fish poisoning

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, 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 T61.77 in its code family, with their registry titles.

View all codes in the T61 family