T43.591SPoisoning by other antipsychotics and neuroleptics, accidental (unintentional), sequela

T43.591S is the ICD-10-CM diagnosis code for poisoning by other antipsychotics and neuroleptics, accidental (unintentional), sequela. It belongs to category T43 (poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified), block T36-T50 (poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances) 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 "S" means sequela: use it for complications or conditions that arise as a direct result of the original 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 922 (Other Injury, Poisoning and Toxic Effect Diagnoses with MCC, relative weight 1.6238) and DRG 923 (Other Injury, Poisoning and Toxic Effect Diagnoses without MCC, relative weight 0.9973), 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 is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

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 909.0 (late effect of poisoning due to drug, medicinal or biological substance) and E929.2 (late effects of accidental poisoning).