2026 ICD-10-CM Diagnosis Code T38Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified

ICD-10-CM Codes›S00–T88›T36-T50›T38

ICD-10-CM T38
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T38 is a non-billable ICD-10-CM category code for poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified, so it cannot be submitted on claims. Use a more specific code from this category instead, such as T38.0X1A, T38.0X1D, T38.0X1S, and T38.0X2A.

Code Identity

ICD-10-CM Code
T38
Billable Status
No — Non-Billable Category
Code Describes
Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified
Chapter
T36-T50
Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT36-T50Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances
CategoryT38Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified
This CodeT38Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified

Specific Coding for Hormones and their synthetic substitutes and antag, NECOverview

Non-specific codes like T38 require more characters. Use one of these billable codes instead:

  • T38.0 for Poisoning by, adverse effect of and underdosing of glucocorticoids and synthetic analogues

  • T38.0X for Poisoning by, adverse effect of and underdosing of glucocorticoids and synthetic analogues

  • T38.1 for Poisoning by, adverse effect of and underdosing of thyroid hormones and substitutes

  • T38.1X for Poisoning by, adverse effect of and underdosing of thyroid hormones and substitutes

  • T38.2 for Poisoning by, adverse effect of and underdosing of antithyroid drugs

  • T38.2X for Poisoning by, adverse effect of and underdosing of antithyroid drugs

  • T38.3 for Poisoning by, adverse effect of and underdosing of insulin and oral hypoglycemic [antidiabetic] drugs

  • T38.3X for Poisoning by, adverse effect of and underdosing of insulin and oral hypoglycemic [antidiabetic] drugs

  • T38.4 for Poisoning by, adverse effect of and underdosing of oral contraceptives

  • T38.4X for Poisoning by, adverse effect of and underdosing of oral contraceptives

  • T38.5 for Poisoning by, adverse effect of and underdosing of other estrogens and progestogens

  • T38.5X for Poisoning by, adverse effect of and underdosing of other estrogens and progestogens

  • T38.6 for Poisoning by, adverse effect of and underdosing of antigonadotrophins, antiestrogens, antiandrogens, not elsewhere classified

  • T38.6X for Poisoning by, adverse effect of and underdosing of antigonadotrophins, antiestrogens, antiandrogens, not elsewhere classified

  • T38.7 for Poisoning by, adverse effect of and underdosing of androgens and anabolic congeners

  • T38.7X for Poisoning by, adverse effect of and underdosing of androgens and anabolic congeners

  • T38.8 for Poisoning by, adverse effect of and underdosing of other and unspecified hormones and synthetic substitutes

  • T38.80 for Poisoning by, adverse effect of and underdosing of unspecified hormones and synthetic substitutes

  • T38.81 for Poisoning by, adverse effect of and underdosing of anterior pituitary [adenohypophyseal] hormones

  • T38.89 for Poisoning by, adverse effect of and underdosing of other hormones and synthetic substitutes

  • T38.9 for Poisoning by, adverse effect of and underdosing of other and unspecified hormone antagonists

  • T38.90 for Poisoning by, adverse effect of and underdosing of unspecified hormone antagonists

  • T38.99 for Poisoning by, adverse effect of and underdosing of other hormone antagonists

Coding GuidelinesGuidance

When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.

The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified (T38). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Tabular List NotesGuidance

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

Type 1 Excludes

  • mineralocorticoids and their antagonists T50.0
  • oxytocic hormones T48.0
  • parathyroid hormones and derivatives T50.9

7th Character Note

  • The appropriate 7th character is to be added to each code from category T38

7th Character

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Patient EducationClinical

Drug Reactions

Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.

The full article covers:

  • What is a drug interaction?
  • What are side effects?
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  • How can I stay safe when taking medicines?

Read the full article at MedlinePlus

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

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 T38Overview

Is T38 a billable code?

No. This is a category header that groups the codes for poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified, and headers cannot be submitted on claims. Claims for poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified need a more specific code from this category, such as T38.0X1A, T38.0X1D, and T38.0X1S.