2026 ICD-10-CM Diagnosis Code T36.AX2APoisoning by fluoroquinolone antibiotics, intentional self-harm, initial encounter
T36.AX2A is a billable ICD-10-CM diagnosis code for poisoning by fluoroquinolone antibiotics, intentional self-harm, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 917 through 918.
Code Identity
Code Classification
Coding GuidelinesGuidance
When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of systemic antibiotics (T36). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Table of Drugs and ChemicalsClinical
Code History & ChangesHistory
New Code T36.AX2A was added to the ICD-10-CM code set for FY 2026, effective October 1, 2025.
Replacement T36.AX2A replaces the following previously assigned code(s):
- T36.8X2A - Poisoning by oth systemic antibiotics, self-harm, init
Questions About T36.AX2AOverview
Is T36.AX2A a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by fluoroquinolone antibiotics, intentional self-harm, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T36.AX2A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for poisoning by fluoroquinolone antibiotics, intentional self-harm, such as an emergency visit or first evaluation.
What MS-DRG does T36.AX2A group to?
When poisoning by fluoroquinolone antibiotics, intentional self-harm, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.
