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ICD-10-CM · FY 2026 APRIL UPDATE

T40.41

Poisoning by, adverse effect of and underdosing of fentanyl or fentanyl analogs

Diagnosis reference

Nonbillable category

This entry is a category or subcategory. Choose the appropriate billable descendant based on the clinical documentation.

Effective periodOctober 1, 2026–September 30, 2027
SourceCMS ICD-10-CM order file
ClassificationDiagnosis · clinical modification

Related entries

Up to 30 descendants in this category

CODEDESCRIPTIONTYPE
T40.411Poisoning by fentanyl or fentanyl analogs, accidental (unintentional)Category
T40.411APoisoning by fentanyl or fentanyl analogs, accidental (unintentional), initial encounterBillable
T40.411DPoisoning by fentanyl or fentanyl analogs, accidental (unintentional), subsequent encounterBillable
T40.411SPoisoning by fentanyl or fentanyl analogs, accidental (unintentional), sequelaBillable
T40.412Poisoning by fentanyl or fentanyl analogs, intentional self-harmCategory
T40.412APoisoning by fentanyl or fentanyl analogs, intentional self-harm, initial encounterBillable
T40.412DPoisoning by fentanyl or fentanyl analogs, intentional self-harm, subsequent encounterBillable
T40.412SPoisoning by fentanyl or fentanyl analogs, intentional self-harm, sequelaBillable
T40.413Poisoning by fentanyl or fentanyl analogs, assaultCategory
T40.413APoisoning by fentanyl or fentanyl analogs, assault, initial encounterBillable
T40.413DPoisoning by fentanyl or fentanyl analogs, assault, subsequent encounterBillable
T40.413SPoisoning by fentanyl or fentanyl analogs, assault, sequelaBillable
T40.414Poisoning by fentanyl or fentanyl analogs, undeterminedCategory
T40.414APoisoning by fentanyl or fentanyl analogs, undetermined, initial encounterBillable
T40.414DPoisoning by fentanyl or fentanyl analogs, undetermined, subsequent encounterBillable
T40.414SPoisoning by fentanyl or fentanyl analogs, undetermined, sequelaBillable
T40.415Adverse effect of fentanyl or fentanyl analogsCategory
T40.415AAdverse effect of fentanyl or fentanyl analogs, initial encounterBillable
T40.415DAdverse effect of fentanyl or fentanyl analogs, subsequent encounterBillable
T40.415SAdverse effect of fentanyl or fentanyl analogs, sequelaBillable
T40.416Underdosing of fentanyl or fentanyl analogsCategory
T40.416AUnderdosing of fentanyl or fentanyl analogs, initial encounterBillable
T40.416DUnderdosing of fentanyl or fentanyl analogs, subsequent encounterBillable
T40.416SUnderdosing of fentanyl or fentanyl analogs, sequelaBillable

Use the complete reference

This reference does not reproduce the full tabular hierarchy, inclusion notes, Excludes1/2 notes, sequencing instructions, or seventh-character rules. Review the official tables and coding guidelines.

Open official CMS files

ICD-10-CM codes describe diagnoses. They do not have an independent Medicare PFS reimbursement amount, and billability alone does not establish coverage.