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A05.1 ICD-10-CM Code: Botulism food poisoning

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
2 inclusion terms · 7 Excludes1

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.

  • MS-DRG 867 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITH MCC (MDC 18)
  • MS-DRG 868 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITH CC (MDC 18)
  • MS-DRG 869 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITHOUT CC/MCC (MDC 18)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for A05.1 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on A05.1 itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Botulism NOS
  • Classical foodborne intoxication due to Clostridium botulinum

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).

Coder workflow for A05.1

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

Before you code A05.1

  1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with A05.1. 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 a condition named in A05.1’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.

    ReviewA48.51, A48.52, A04.7, A32, A02

Consider A05.1. Then 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).

Official instructions as workflow

  • Excludes1 — check before selecting A05.1(7 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with A05.1: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareA48.51, A48.52, A04.7, A32, A02

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

Coding decision scenarios

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

Documentation: Both the condition A05.1 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).

ReviewA48.51, A48.52, A04.7, A32, A02

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

Botulism food poisoning is a billable ICD-10-CM diagnosis code (A05.1).

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

Indexed Clinical Terms (9)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Verify Before Coding

  • CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

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 A05.1 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 6 Excludes1 notes across 3 chapters: A04 — Other bacterial intestinal infections (via A05.-), A48.5 — Other specified botulism, G70 — Myasthenia gravis and other myoneural disorders, T61 — Toxic effect of noxious substances eaten as seafood (via A05.-), T62 — Toxic effect of other noxious substances eaten as food (via A05.-), T78.1 — Other adverse food reactions, not elsewhere classified (via A05.-).

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

Referenced by 6 Excludes2 notes: P35 — Congenital viral diseases (via A05.-), P35-P39 — Infections specific to the perinatal period (P35-P39) (via A05.-), P36 — Bacterial sepsis of newborn (via A05.-), P37 — Other congenital infectious and parasitic diseases (via A05.-), P38 — Omphalitis of newborn (via A05.-), P39 — Other infections specific to the perinatal period (via A05.-).

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

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 7 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 867 (MDC 18), DRG 868 (MDC 18), DRG 869 (MDC 18).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):INF005 — Foodborne intoxications (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

A04.71 — Enterocolitis due to Clostridium difficile, recurrent, A04.72 — Enterocolitis due to Clostridium difficile, not specified as recurrent, A05.0 — Foodborne staphylococcal intoxication, A05.2 — Foodborne Clostridium perfringens [Clostridium welchii] intoxication, A48.51 — Infant botulism, A48.52 — Wound botulism

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Foodborne intoxications).

A05.0 — Foodborne staphylococcal intoxication, A05.2 — Foodborne Clostridium perfringens [Clostridium welchii] intoxication, A05.3 — Foodborne Vibrio parahaemolyticus intoxication, A05.4 — Foodborne Bacillus cereus intoxication, A05.5 — Foodborne Vibrio vulnificus intoxication, A05.8 — Other specified bacterial foodborne intoxications, A05.9 — Bacterial foodborne intoxication, unspecified, A48.51 — Infant botulism

Same Index main term, other category

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

A04.1 — Enterotoxigenic Escherichia coli infection (infectious NOS, due to, Escherichia coli, enterotoxigenic), A04.2 — Enteroinvasive Escherichia coli infection (infectious NOS, due to, Escherichia coli, enteroinvasive), A04.3 — Enterohemorrhagic Escherichia coli infection (infectious NOS, due to, Escherichia coli, enterohemorrhagic), A04.4 — Other intestinal Escherichia coli infections (infectious NOS, due to, Escherichia coli), A04.5 — Campylobacter enteritis (infectious NOS, due to, Campylobacter), A04.6 — Enteritis due to Yersinia enterocolitica (due to, Yersinia enterocolitica), A04.71 — Enterocolitis due to Clostridium difficile, recurrent (Clostridium, difficile, recurrent), A04.72 — Enterocolitis due to Clostridium difficile, not specified as recurrent (Clostridium, difficile, not specified as recurrent), A04.8 — Other specified bacterial intestinal infections (staphylococcal), A04.9 — Bacterial intestinal infection, unspecified (bacterial), A06.0 — Acute amebic dysentery (amebic), A06.1 — Chronic intestinal amebiasis (amebic, chronic), A06.2 — Amebic nondysenteric colitis (amebic, nondysenteric), A07.1 — Giardiasis [lambliasis] (giardial), A07.3 — Isosporiasis (coccidial), A07.8 — Other specified protozoal intestinal diseases (trichomonal), A07.9 — Protozoal intestinal disease, unspecified (protozoal), A08.0 — Rotaviral enteritis (rotaviral), A08.11 — Acute gastroenteropathy due to Norwalk agent (norovirus), A08.19 — Acute gastroenteropathy due to other small round viruses (small round structured NEC), +91 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Fecal Occult Blood Test (FOBT)

Contextual Map

Every relationship of A05.1 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 A05.1 with these 14 related codes in Claim Check

Hierarchy

Excludes1

  • A48.51 — Infant botulism[Excludes1]: “infant botulism (A48.51)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
  • A48.52 — Wound botulism[Excludes1]: “wound botulism (A48.52)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes1 notes

Referenced by Excludes2 notes

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 18 — Infectious and Parasitic Diseases, Systemic or Unspecified Sites[MDC crossing]: “Infectious and Parasitic Diseases, Systemic or Unspecified Sites — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 1 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries (9)

  • Botulism (foodborne intoxication)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective), Clostridium, botulinum (food poisoning)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Infection, infected, infective (opportunistic), Clostridium NEC, botulinum (food poisoning)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Intoxication, foodborne, classical (Clostridium botulinum)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Intoxication, foodborne, due to, Clostridium, botulinum[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Poisoning (acute), Bacillus B (aertrycke) (cholerae (suis)) (paratyphosus) (suipestifer), botulinus[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Poisoning (acute), botulism[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Poisoning (acute), Clostridium botulinum[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • and 1 more

Nearest codes

Change history

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

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
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 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

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. "A05.1 — Botulism food poisoning." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/a05.1-botulism-food-poisoning

Change history

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

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 A05.1 in its code family, with their registry titles.

View all codes in the A05 family