T23.421A
✓ BillableCorrosion of unspecified degree of single right finger (nail) except thumb, initial encounter
Injury, poisoning and certain other consequences of external causes (S00-T88)
📋 Code Instructions
inherited- • external cause code to identify place (Y92)
- • Code first: (T51-T65) to identify chemical and intent
Clinical Description
ICD-10-CM code T23.421A represents corrosion of unspecified degree of single right finger (nail) except thumb, initial encounter. This code falls under the Injury, poisoning and certain other consequences of external causes (S00-T88) classification. It is a billable/specific code valid for HIPAA-covered transactions as of October 1, 2025 (FY2026). This code can be used to indicate a diagnosis for reimbursement purposes on insurance claims.
This is a 8-character code at the 7th level of specificity. This is the most specific code available in this subcategory.
Frequently Asked Questions
What is ICD-10 code T23.421A?
ICD-10-CM code T23.421A is "Corrosion of unspecified degree of single right finger (nail) except thumb, initial encounter". It belongs to the category: Injury, poisoning and certain other consequences of external causes (S00-T88).
Is T23.421A a billable ICD-10 code?
Yes, T23.421A is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
Related Codes in T23.421
Other codes in the same category that may be relevant for differential coding:
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Data Source
CMS ICD-10-CM 2026 Tabular List
Updated October 1, 2025 (FY2026)