T59.821A — Toxic effect of hexamethylene diisocyanate, accidental (unintentional), initial encounter
Is T59.821A billable?
Yes — T59.821A is billable for FY2027. T59.821A is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T59.821A may be submitted for encounters from October 1, 2026 through September 30, 2027. T59.821A is new in FY2027.
T59.821A at a glance
| Code | T59.821A |
|---|---|
| Description | Toxic effect of hexamethylene diisocyanate, accidental (unintentional), initial encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter |
| FY2027 change | New in FY2027 |
What does the 7th character "A" mean in T59.821A?
In T59.821A, the 7th character A means initial encounter. The 7th character is required for T59.821A to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does T59.821A group to?
T59.821A sits in MDC 21 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 917Poisoning and Toxic Effects of Drugs with MCCmedical
- 918Poisoning and Toxic Effects of Drugs without MCCmedical
Inclusion terms
Alternative wording in documentation that is classified to T59.821A.
- Toxic effects of hexamethylene diisocyanate NOS
Excludes1 — never code together — inherited from T51-T65
The conditions below can never be reported together with T59.821A on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- contact with and (suspected) exposure to toxic substances (Z77.-)
Excludes1 — never code together — inherited from T59
The conditions below can never be reported together with T59.821A on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- chlorofluorocarbons (T53.5)
Use additional code — inherited from Chapter 19
Report an additional code alongside T59.821A to fully describe the condition. T59.821A is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Use additional code — inherited from T51-T65
Report an additional code alongside T59.821A to fully describe the condition. T59.821A is sequenced first.
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T59.821A, but a patient may have both at the same time. When documentation supports it, T59.821A and the excluded code may both be reported.