ICD-10-CM 2027 diagnosis code
T65.221AToxic effect of tobacco cigarettes, accidental (unintentional), initial encounter
T65.221A is a valid, billable ICD-10-CM code for toxic effect of tobacco cigarettes, accidental (unintentional), initial encounter. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Toxic effect of tobacco cigarettes, accidental, init
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 T65.221A
T65.221A is the ICD-10-CM diagnosis code for toxic effect of tobacco cigarettes, accidental (unintentional), initial encounter. It belongs to category T65 (toxic effect of other and unspecified substances), block T51-T65 (toxic effects of substances chiefly nonmedicinal as to source) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
The 7th character "A" means initial encounter: use it while the patient is receiving active treatment for the condition.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 917 (Poisoning and Toxic Effects of Drugs with MCC, relative weight 1.57) and DRG 918 (Poisoning and Toxic Effects of Drugs without MCC, relative weight 0.872), in MDC 21 (Injuries, Poisonings and Toxic Effects of Drugs), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 989.84 (toxic effect of tobacco) and E866.8 (accidental poisoning by other specified solid or liquid substances).
7th character
Ainitial encounter
Other encounter types for T65.221:
Notes that apply from higher levels
Instructions written at a parent level also apply to T65.221A.
› From T65.2 Toxic effect of tobacco and nicotine
- nicotine dependence (F17.-)
Broader instructions also apply from T51-T65 Toxic effects of substances chiefly nonmedicinal as to source and Chapter 19: Injury, poisoning and certain other consequences of external causes.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 21 · Injuries, Poisonings and Toxic Effects of Drugs
ICD-9-CM equivalent
Converter →- 989.84Toxic effect of tobaccoapproximate, combination
- E866.8Accidental poisoning by other specified solid or liquid substancesapproximate, combination
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
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 T65.221A
Is T65.221A billable?
- Yes. T65.221A is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
What does the "A" at the end of T65.221A mean?
- It is the 7th character for initial encounter. Per the official guidelines, use it while the patient is receiving active treatment for the condition.
Can T65.221A be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict T65.221A as a principal diagnosis.
Is T65.221A a CC or MCC?
- No. T65.221A is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does T65.221A group to?
- T65.221A is used in the MS-DRG v44.0 logic for MS-DRG 917 (Poisoning and Toxic Effects of Drugs with MCC) and MS-DRG 918 (Poisoning and Toxic Effects of Drugs without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.