ICD-10-CM 2027 diagnosis code
T50.90Poisoning by, adverse effect of and underdosing of unspecified drugs, medicaments and biological substances
T50.90 is a header code, so it can't be reported by itself. Choose one of the 6 more specific codes beneath it and add the required 7th character.Short description: Unsp drugs, medicaments and biological substances
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 T50.90
T50.90 is the ICD-10-CM diagnosis code for poisoning by, adverse effect of and underdosing of unspecified drugs, medicaments and biological substances. It belongs to category T50 (poisoning by, adverse effect of and underdosing of diuretics and other and unspecified drugs, medicaments and biological substances), 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 6 subcodes must be used instead.
Within T50.9, choose T50.90 (unspecified drugs, medicaments and biological substances) only when documentation doesn't support a more specific option: multiple unspecified drugs, medicaments and biological substances (T50.91) and other drugs, medicaments and biological substances (T50.99).
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 T50
- T50.901Poisoning by unspecified drugs, medicaments and biological substances, accidental (unintentional)
- T50.902Poisoning by unspecified drugs, medicaments and biological substances, intentional self-harm
- T50.903Poisoning by unspecified drugs, medicaments and biological substances, assault
- T50.904Poisoning by unspecified drugs, medicaments and biological substances, undetermined
- T50.905Adverse effect of unspecified drugs, medicaments and biological substances
- T50.906Underdosing of unspecified drugs, medicaments and biological substances
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Notes that apply from higher levels
Instructions written at a parent level also apply to T50.90.
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 T50.90
Is T50.90 billable?
- No. T50.90 is a header code. Report one of its more specific subcodes instead.