R43.1 ICD-10-CM Code: Parosmia

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for R43.1 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 R43.1 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for R43.1

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

Before you code R43.1

1. Check whether an established diagnosis that explains this sign or symptom is documented. If one is, review whether the documented diagnosis changes the coding pathway: a symptom that is integral to a confirmed diagnosis is not reported separately, while one not routinely associated with it may be. Signs and symptoms are reported when no definitive diagnosis is established (Guidelines I.B.4, I.B.5, I.B.6, I.C.18.b).

   Guide: Symptom code vs confirmed diagnosis →

Choose the right path

1. Is an established diagnosis that explains this sign or symptom documented?
   Yes → Review whether the documented diagnosis changes the coding pathway: a symptom integral to it is not reported separately.
   No → Continue — the sign or symptom code stands when no definitive diagnosis is established.

Consider R43.1. 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

• Excludes2 — not part of R43.1(1 note)

  Coding workflow: The conditions named in this note are not included in R43.1. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

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

Coding decision scenarios

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

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.

Indexed Clinical Terms (5)

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.

• Disorder (of), sense of smell
• Disturbance (s), olfactory nerve
• Disturbance (s), sensation NEC (cold) (heat) (localization) (tactile discrimination) (texture) (vibratory), smell, parosmia
• Hyperosmia
• Parosmia

Don’t confuse R43.1 with…

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

The codes most likely to be picked instead of R43.1 — 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.

• R43.9— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Unspecified disturbances of smell and taste” takes R43.9; specificity in the record moves it back here.

  Full comparison: R43.1 vs R43.9 →

• F01— 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 symptoms and signs constituting part of a pattern of mental disorder adds F01; it is not part of this code and both may be reported when both are documented.

  Full comparison: R43.1 vs F01 →

• F99— 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 symptoms and signs constituting part of a pattern of mental disorder adds F99; it is not part of this code and both may be reported when both are documented.

  Full comparison: R43.1 vs F99 →

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.

Verify Before Coding

• No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

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

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 3 MS-DRGs: DRG 091 (MDC 01), DRG 092 (MDC 01), DRG 093 (MDC 01).

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

Clinical classification (AHRQ CCSR):SYM010 — Nervous system signs and symptoms (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 category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Nervous system signs and symptoms).

R41.83 — Borderline intellectual functioning, R41.840 — Attention and concentration deficit, R41.841 — Cognitive communication deficit, R41.842 — Visuospatial deficit, R41.843 — Psychomotor deficit, R41.844 — Frontal lobe and executive function deficit, R41.85 — Anosognosia, R41.89 — Other symptoms and signs involving cognitive functions and awareness, R41.9 — Unspecified symptoms and signs involving cognitive functions and awareness, R43.0 — Anosmia, R43.2 — Parageusia, R43.8 — Other disturbances of smell and taste, R43.9 — Unspecified disturbances of smell and taste, R47.01 — Aphasia, R47.02 — Dysphasia, R47.1 — Dysarthria and anarthria, R47.81 — Slurred speech, R47.82 — Fluency disorder in conditions classified elsewhere, R47.89 — Other speech disturbances, R47.9 — Unspecified speech disturbances, +138 more

Same Index main term, other category

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

P74.8 — Other transitory metabolic disturbances of newborn (metabolism, neonatal, transitory, specified NEC), P74.9 — Transitory metabolic disturbance of newborn, unspecified (metabolism, neonatal, transitory), P81.8 — Other specified disturbances of temperature regulation of newborn (temperature, regulation, newborn, specified NEC), P81.9 — Disturbance of temperature regulation of newborn, unspecified (temperature, regulation, newborn), P91.88 — Other specified disturbances of cerebral status of newborn (cerebral, status, newborn, specified NEC), P91.9 — Disturbance of cerebral status of newborn, unspecified (cerebral, status, newborn), R20.0 — Anesthesia of skin (sensation NEC, skin, anesthesia), R20.1 — Hypoesthesia of skin (sensation NEC, skin, hypoesthesia), R20.2 — Paresthesia of skin (sensation NEC, skin, paresthesia), R20.3 — Hyperesthesia (sensation NEC, skin, hyperesthesia), R20.8 — Other disturbances of skin sensation (temperature, sense), R20.9 — Unspecified disturbances of skin sensation (sensation NEC), R27.8 — Other lack of coordination (coordination), R29.2 — Abnormal reflex (motor), R42 — Dizziness and giddiness (equilibrium), R45.0 — Nervousness (nervous, functional), R47.89 — Other speech disturbances (speech, specified NEC), R47.9 — Unspecified speech disturbances (speech), R49.8 — Other voice and resonance disorders (voice, specified NEC), R49.9 — Unspecified voice and resonance disorder (voice), +128 more

Contextual Map

Every relationship of R43.1 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.

Hierarchy

• R00-R99 — Chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) (R00-R99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• R40-R46 — Symptoms and signs involving cognition, perception, emotional state and behavior[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Clinical classification (CCSR)

• SYM010 — Nervous system signs and symptoms[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• DRG 091 — OTHER DISORDERS OF NERVOUS SYSTEM WITH MCC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITH MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 092 — OTHER DISORDERS OF NERVOUS SYSTEM WITH CC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITH CC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 093 — OTHER DISORDERS OF NERVOUS SYSTEM WITHOUT CC/MCC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITHOUT CC/MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — 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. 8,892 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

• Disorder (of), sense of smell[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Disturbance (s), olfactory nerve[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Disturbance (s), sensation NEC (cold) (heat) (localization) (tactile discrimination) (texture) (vibratory), smell, parosmia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Hyperosmia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Parosmia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes

• R43 — Disturbances of smell and taste[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• R43.0 — Anosmia[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• R43.2 — Parageusia[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• R43.8 — Other disturbances of smell and taste[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• R43.9 — Unspecified disturbances of smell and taste[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

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

Nearest Codes in This Family

Official ICD-10-CM classifications closest to R43.1 in its code family, with their registry titles.

• R43 — Disturbances of smell and taste
• R43.0 — Anosmia
• R43.2 — Parageusia
• R43.8 — Other disturbances of smell and taste
• R43.9 — Unspecified disturbances of smell and taste

View all codes in the R43 family