R18 Ascites

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Ascites is R18 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
R10-R19: Symptoms and signs involving the digestive system and abdomen (R10-R19)
Category R18
3 codes (2 billable)
FY2026 Status
Stable since FY2024
Includes
  • fluid in peritoneal cavity
Excludes1
Not coded here. These conditions should NOT be coded together with R18.
  • ascites in alcoholic cirrhosis (K70.31)
  • ascites in alcoholic hepatitis (K70.11)
  • ascites in toxic liver disease with chronic active hepatitis (K71.51)

Official Coding Guidelines

Repeated falls vs history of falling

d. Repeated falls Code R29.6, Repeated falls, is for use for encounters when a patient has recently fallen and the reason for the fall is being investigated. Code Z91.81, History of falling, is for use when a patient has fallen in the past and is at risk for future falls. When appropriate, both codes R29.6 and Z91.81 may be assigned together.

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.18.d
Use of R40.20 unspecified coma; do not report for induced/sedated

e. Coma Code R40.20, Unspecified coma, should be assigned when the underlying cause of the coma is not known, or the cause is a traumatic brain injury and the coma scale is not documented in the medical record. Do not report codes for unspecified coma, individual or total Glasgow coma scale scores for a patient with a medically induced coma or a sedated patient.

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.18.e

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference R18 with the canonical source and edition:

R18 — Ascites. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/R18

Canonical URL: https://icd10codingpro.com/codes/R18

Related Codes

All Codes in R18

Every most-specific code under R18 Ascites (2 codes):

Show the complete R18 code list
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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