ICD-10-CM 2027 diagnosis code
T44.6Poisoning by, adverse effect of and underdosing of alpha-adrenoreceptor antagonists
T44.6 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: Alpha-adrenoreceptor antagonists
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 T44.6
T44.6 is the ICD-10-CM diagnosis code for poisoning by, adverse effect of and underdosing of alpha-adrenoreceptor antagonists. It belongs to category T44 (poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system), 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 T44 (poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system), T44.6 is specifically for poisoning by, adverse effect of and underdosing of alpha-adrenoreceptor antagonists. Related codes cover anticholinesterase agents (T44.0), other parasympathomimetics [cholinergics] (T44.1), ganglionic blocking drugs (T44.2), other parasympatholytics [anticholinergics and antimuscarinics] and spasmolytics (T44.3), predominantly alpha-adrenoreceptor agonists (T44.4), predominantly beta-adrenoreceptor agonists (T44.5), beta-adrenoreceptor antagonists (T44.7), centrally-acting and adrenergic-neuron- blocking agents (T44.8) 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.
Don't report T44.6 together with the conditions in its Excludes1 note: poisoning by, adverse effect of and underdosing of ergot alkaloids (T48.0).
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 T44
- T44.6XPoisoning by, adverse effect of and underdosing of alpha-adrenoreceptor antagonists
- T44.6X1Poisoning by alpha-adrenoreceptor antagonists, accidental (unintentional)
- T44.6X2Poisoning by alpha-adrenoreceptor antagonists, intentional self-harm
- T44.6X3Poisoning by alpha-adrenoreceptor antagonists, assault
- T44.6X4Poisoning by alpha-adrenoreceptor antagonists, undetermined
- T44.6X5Adverse effect of alpha-adrenoreceptor antagonists
- T44.6X6Underdosing of alpha-adrenoreceptor antagonists
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Coding notes
- poisoning by, adverse effect of and underdosing of ergot alkaloids (T48.0)
Notes that apply from higher levels
Instructions written at a parent level also apply to T44.6.
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 T44.6
Is T44.6 billable?
- No. T44.6 is a header code. Report one of its more specific subcodes instead.