2026 ICD-10-CM Diagnosis Code E16.2Hypoglycemia, unspecified

ICD-10-CM CodesE00–E89E15-E16E16

ICD-10-CM E16.2
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E16.2 is a billable ICD-10-CM diagnosis code for hypoglycemia, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 640 through 641. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified endocrine disorders.

Code Identity

ICD-10-CM Code
E16.2
Billable Status
Yes — Valid for Submission
Code Describes
Hypoglycemia, unspecified
Short Description
Hypoglycemia, unspecified
Same as the full description in the CMS dataset.
Parent Code
Other disorders of pancreatic internal secretion

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE15-E16Other disorders of glucose regulation and pancreatic internal secretion
CategoryE16Other disorders of pancreatic internal secretion
This CodeE16.2Hypoglycemia, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Adult onset non-insulinoma persistent hyperinsulinemic hypoglycemia
  • Blood glucose below reference range
  • Glucose level below reference range
  • Glycopenia
  • Hypoglycemia
  • Hypoglycemia-induced convulsion
  • Hypoglycemic disorder
  • Hypoglycemic encephalopathy
  • Hypoglycemic shock
  • Hypoglycemic syndrome
  • Neuropathy associated with hypoglycemia
  • Nocturnal hypoglycemia
  • Nocturnal hypoglycemia due to diabetes mellitus
  • Non-diabetic hypoglycemia
  • Random blood glucose outside reference range
  • Random blood sugar below reference range
  • Random glucose level abnormal
  • Sequelae of endocrine disorders
  • Situation-related seizures
  • Spontaneous hypoglycemia

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code for hypoglycemia level, if applicable E16.A

Type 1 Excludes

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Decrease(d)
      • blood
        • glucose
    • Decrease(d)
      • glucose
    • Encephalopathy(acute)
      • hypoglycemic
    • Findings, abnormal, inconclusive, without diagnosis
      • blood sugar
        • low (transient)
    • Glycopenia
    • Hypoglycemia(spontaneous)
    • McQuarrie's syndrome(idiopathic familial hypoglycemia)
    • Polyneuropathy(peripheral)
      • in (due to)
        • hypoglycemia
    • Sugar
      • blood
        • low (transient)
    • Syndrome
      • hypoglycemic (familial) (neonatal)
    • Syndrome
      • McQuarrie's

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR END015
Other specified and unspecified endocrine disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Congenital Hyperinsulinism

    a familial, nontransient hypoglycemia with defects in negative feedback of glucose-regulated insulin release. clinical phenotypes include hypoglycemia; hyperinsulinemia; seizures; coma; and often large birth weight. several sub-types exist with the most common, type 1, associated with mutations on an atp-binding cassette transporters (subfamily c, member 8).
  • Hypoglycemia

    a syndrome of abnormally low blood glucose level. clinical hypoglycemia has diverse etiologies. severe hypoglycemia eventually lead to glucose deprivation of the central nervous system resulting in hunger; sweating; paresthesia; impaired mental function; seizures; coma; and even death.

Patient EducationClinical

Hypoglycemia

Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your bloodstream. When your blood glucose goes up, it signals your pancreas to release insulin.

The full article covers:

  • What is blood glucose?
  • What is hypoglycemia?
  • What causes hypoglycemia?
  • What are the symptoms of hypoglycemia?
  • How is hypoglycemia diagnosed?
  • What are the treatments for hypoglycemia?
  • Can hypoglycemia be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert E16.2 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
251.2 Hypoglycemia NOS
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E16.2Overview

Is E16.2 (Other disorders of pancreatic internal secretion) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report hypoglycemia, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does E16.2 group to?

When hypoglycemia, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 640, 641, with relative weights from 0.7782 to 1.3356 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E16.2?

Under the General Equivalence Mappings, hypoglycemia, unspecified converts to ICD-9-CM 251.2 (hypoglycemia NOS). The mapping is a direct match.

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.