2026 ICD-10-CM Diagnosis Code T18.9XXAForeign body of alimentary tract, part unspecified, initial encounter
T18.9XXA is a billable ICD-10-CM diagnosis code for foreign body of alimentary tract, part unspecified, 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 393 through 395. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of foreign body entering opening, initial encounter; External cause codes: intent of injury, accidental/unintentional; and External cause codes: other specified, classifiable and NEC; initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Antacid bezoar
- Bezoar
- Chronic trichobezoar formation
- Food granuloma of intestine
- Foreign body granuloma of intestine
- Foreign body in digestive tract
- Foreign body in intestine
- Granuloma of intestine
- Ingestion of foreign material
- Lactobezoar
- Linear foreign body of gastrointestinal tract
- Medication bezoar
- Phytobezoar
- Swallowed foreign body
- Trichobezoar
- Trichophytobezoar
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Foreign body in alimentary tract (T18). 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
Foreign Bodies
If you've ever gotten a splinter or had sand in your eye, you've had experience with a foreign body. A foreign body is something that is stuck inside you but isn't supposed to be there. You may inhale or swallow a foreign body, or you may get one from an injury to almost any part of your body.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T18.9XXA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T18.9XXAOverview
Is T18.9XXA (Foreign body of alimentary tract, part unspecified) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report foreign body of alimentary tract, part unspecified, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T18.9XXA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for foreign body of alimentary tract, part unspecified, such as an emergency visit or first evaluation.
What MS-DRG does T18.9XXA group to?
When foreign body of alimentary tract, part unspecified, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of T18.9XXA?
Under the General Equivalence Mappings, foreign body of alimentary tract, part unspecified, initial encounter converts to ICD-9-CM 938 (foreign body GI NOS) and E915 (FB entering oth orifice). 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.
