E87.1 Hypo-osmolality and hyponatremia

The ICD-10-CM code for Hypo-osmolality and hyponatremia is E87.1 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

4: Endocrine, nutritional and metabolic diseases (E00-E89)

Section

E70-E88: Metabolic disorders (E70-E88)

Category E87

17 codes (14 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to E87.1:

• Hypo-osmolality
• Hyponatremia
• Cramp (s) › salt-depletion
• Findings, abnormal, inconclusive, without diagnosis › sodium (deficiency)
• Deficiency, deficient › salt
• Deficiency, deficient › sodium (Na)
• Deficiency, deficient › natrium
• Depletion › salt or sodium

Inclusion Terms

• Sodium [Na] deficiency

U.S. Hospital Utilization

• An estimated 3,371,365 U.S. inpatient stays in 2023 included E87.1 among the documented diagnoses.
• 120,155 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Diabetes mellitus (TOC entry)

a. Diabetes mellitus ................................................................................................................... 39

Obesity (TOC entry)

b. Obesity .................................................................................................................................. 42

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

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)