2026 ICD-10-CM Diagnosis Code E23.1Drug-induced hypopituitarism

ICD-10-CM Codes›E00–E89›E20-E35›E23

ICD-10-CM E23.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E23.1 is a billable ICD-10-CM diagnosis code for drug-induced hypopituitarism. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 643 through 645. Coders also document this condition as effects of immunotherapy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Drug induced or toxic related condition and Pituitary disorders.

Code Identity

ICD-10-CM Code
E23.1
Billable Status
Yes — Valid for Submission
Code Describes
Drug-induced hypopituitarism
Short Description
Drug-induced hypopituitarism
Same as the full description in the CMS dataset.
Parent Code
E23
Hypofunction and other disorders of the pituitary gland

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE20-E35Disorders of other endocrine glands
CategoryE23Hypofunction and other disorders of the pituitary gland
This CodeE23.1Drug-induced hypopituitarism

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Effects of immunotherapy
  • Hormone-induced hypopituitarism
  • Hypophysitis caused by drug
  • Hypopituitarism caused by drug
  • Hypopituitarism due to iron overload
  • Hypopituitarism following procedure
  • Iatrogenic hypopituitarism
  • Iatrogenic pituitary disorder
  • Immunotherapy induced hypophysitis

Tabular List NotesGuidance

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

Use Additional Code

  • code for adverse effect, if applicable, to identify drug T36 T50

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.

    • Hypopituitarism(juvenile)
      • drug-induced
    • Hypopituitarism(juvenile)
      • iatrogenic NEC

Clinical ClassificationClinical

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

CCSR INJ030
Drug induced or toxic related condition
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR END013
Pituitary disorders
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Pituitary Disorders

Your pituitary gland is a pea-sized gland at the base of your brain. The pituitary is the "master control gland" - it makes hormones that affect growth and the functions of other glands in the body.

Read the full article at MedlinePlus

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

Convert E23.1 to ICD-9-CMHistory

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

ICD-9-CM
253.7 Iatrogenic pituitary dis
Approximate The match is approximate rather than exact.

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 E23.1Overview

Is E23.1 (Hypofunction and other disorders of the pituitary gland) a billable code?

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

What MS-DRG does E23.1 group to?

When drug-induced hypopituitarism is the principal diagnosis on an inpatient stay, it groups to MS-DRG 643, 644, 645, with relative weights from 0.7683 to 1.6461 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E23.1?

Under the General Equivalence Mappings, drug-induced hypopituitarism converts to ICD-9-CM 253.7 (iatrogenic pituitary dis). 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.