FY2027 ICD-10-CM reference
E87.5: Hyperkalemia
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Hyperkalemia. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Instructional note
All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.
Source: E00-E89 (chapter, inherited).
Excludes1
transitory endocrine and metabolic disorders specific to newborn (P70-P74)
Source: E00-E89 (chapter, inherited).
Excludes1
androgen insensitivity syndrome (E34.5-)
Source: E70-E88 (section, inherited).
Excludes1
congenital adrenal hyperplasia (E25.0)
Source: E70-E88 (section, inherited).
Excludes1
hemolytic anemias attributable to enzyme disorders (D55.-)
Source: E70-E88 (section, inherited).
Excludes1
Marfan syndrome (Q87.4-)
Source: E70-E88 (section, inherited).
Excludes1
5-alpha-reductase deficiency (E29.1)
Source: E70-E88 (section, inherited).
Excludes2
Ehlers-Danlos syndromes (Q79.6-)
Source: E70-E88 (section, inherited).
Excludes1
diabetes insipidus (E23.2)
Source: E87 (category, inherited).
Excludes1
electrolyte imbalance associated with hyperemesis gravidarum (O21.1)
Source: E87 (category, inherited).
Excludes1
electrolyte imbalance following ectopic or molar pregnancy (O08.5)
Source: E87 (category, inherited).
Excludes1
familial periodic paralysis (G72.3)
Source: E87 (category, inherited).
Excludes1
metabolic acidemia in newborn, unspecified (P19.9)
Source: E87 (category, inherited).
Instructional note
Potassium [K] excess
Source: E87.5 (self, direct).
Instructional note
Potassium [K] overload
Source: E87.5 (self, direct).
Compare the FY2027 additions, removals and billable-status changes
What does E87.5 mean in FY2027?
The official ICD-10-CM descriptor is Hyperkalemia. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is E87.5 billable in FY2027?
The FY2027 order file marks E87.5 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does E87.5 map to an HCC?
E87.5 has no CMS-HCC V28 category in the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service). ESRD, RxHCC, PACE and HHS-HCC mappings are still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Read the FY2027 Official Guidelines.
Review the FY2026 April edition