2026 ICD-10-CM Diagnosis Code S50.862AInsect bite (nonvenomous) of left forearm, initial encounter
S50.862A is a billable ICD-10-CM diagnosis code for insect bite (nonvenomous) of left forearm, 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. Coders also document this condition as infected wound of left forearm due to non venomous insect bite. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Infected wound of left forearm due to non venomous insect bite
- Insect bite, nonvenomous, of forearm
- Nonvenomous insect bite of forearm with infection
- Superficial injury of left forearm
- Wound of left forearm due to nonvenomous insect bite
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Superficial injury of elbow and forearm (S50). 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.
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 S50.862A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S50.862AOverview
Is S50.862A (Insect bite (nonvenomous) of left forearm) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report insect bite (nonvenomous) of left forearm, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S50.862A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for insect bite (nonvenomous) of left forearm, such as an emergency visit or first evaluation.
What MS-DRG does S50.862A group to?
When insect bite (nonvenomous) of left forearm, 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 S50.862A?
Under the General Equivalence Mappings, insect bite (nonvenomous) of left forearm, initial encounter converts to ICD-9-CM 913.4 (insect bite forearm). 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.
