2026 ICD-10-CM Diagnosis Code S00.562AInsect bite (nonvenomous) of oral cavity, initial encounter

ICD-10-CM CodesS00–T88S00-S09S00

ICD-10-CM S00.562A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S00.562A is a billable ICD-10-CM diagnosis code for insect bite (nonvenomous) of oral cavity, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607, 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.

Code Identity

ICD-10-CM Code
S00.562A
Billable Status
Yes — Valid for Submission
Code Describes
Insect bite (nonvenomous) of oral cavity, initial encounter
Short Description
Insect bite (nonvenomous) of oral cavity, initial encounter
Same as the full description in the CMS dataset.
Parent Code
Insect bite (nonvenomous) of oral cavity

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS00-S09Injuries to the head
CategoryS00Superficial injury of head
This CodeS00.562AInsect bite (nonvenomous) of oral cavity, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Insect bite of mouth
  • Nonvenomous insect bite of gum
  • Nonvenomous insect bite of gum with infection
  • Nonvenomous insect bite of mouth
  • Nonvenomous insect bite of tongue
  • Nonvenomous insect bite of tongue with infection
  • Superficial injury of gum with infection
  • Superficial injury of tongue

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Superficial injury of head (S00). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ017
Superficial injury; contusion, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Insect Bites and Stings

Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, some mosquitoes spread West Nile virus.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert S00.562A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
910.4 Insect bite head
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About S00.562AOverview

Is S00.562A (Insect bite (nonvenomous) of oral cavity) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report insect bite (nonvenomous) of oral cavity, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S00.562A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for insect bite (nonvenomous) of oral cavity, such as an emergency visit or first evaluation.

What MS-DRG does S00.562A group to?

When insect bite (nonvenomous) of oral cavity, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, 963, 964, 965, with relative weights from 0.9064 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of S00.562A?

Under the General Equivalence Mappings, insect bite (nonvenomous) of oral cavity, initial encounter converts to ICD-9-CM 910.4 (insect bite head). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.