ICD-10-CM 2027 diagnosis code
T38.2Poisoning by, adverse effect of and underdosing of antithyroid drugs
T38.2 is a header code, so it can't be reported by itself. Choose one of the 1 more specific codes beneath it and add the required 7th character.Short description: Antithyroid drugs
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About T38.2
T38.2 is the ICD-10-CM diagnosis code for poisoning by, adverse effect of and underdosing of antithyroid drugs. It belongs to category T38 (poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified), block T36-T50 (poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 1 subcodes must be used instead.
Within T38 (poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified), T38.2 is specifically for poisoning by, adverse effect of and underdosing of antithyroid drugs. Related codes cover glucocorticoids and synthetic analogues (T38.0), thyroid hormones and substitutes (T38.1), insulin and oral hypoglycemic [antidiabetic] drugs (T38.3), oral contraceptives (T38.4), other estrogens and progestogens (T38.5), antigonadotrophins, antiestrogens, antiandrogens, not elsewhere classified (T38.6), androgens and anabolic congeners (T38.7), other and unspecified hormones and synthetic substitutes (T38.8) and 1 more.
Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
7th character
The appropriate 7th character is to be added to each code from category T38
- T38.2XPoisoning by, adverse effect of and underdosing of antithyroid drugs
- T38.2X1Poisoning by antithyroid drugs, accidental (unintentional)
- T38.2X2Poisoning by antithyroid drugs, intentional self-harm
- T38.2X3Poisoning by antithyroid drugs, assault
- T38.2X4Poisoning by antithyroid drugs, undetermined
- T38.2X5Adverse effect of antithyroid drugs
- T38.2X6Underdosing of antithyroid drugs
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Notes that apply from higher levels
Instructions written at a parent level also apply to T38.2.
Broader instructions also apply from T36-T50 Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances and Chapter 19: Injury, poisoning and certain other consequences of external causes.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about T38.2
Is T38.2 billable?
- No. T38.2 is a header code. Report one of its more specific subcodes instead.