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Compare/O29.3 vs T45

O29.3 vs T45

O29.3 (Toxic reaction to local anesthesia during pregnancy) compared with T45 (Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.

Can these codes be reported together?

No — do not report together. T45 carries an Excludes1 note covering O29.3: “toxic reaction to local anesthesia in pregnancy (O29.3-)”

Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Side by side

O29.3Toxic reaction to local anesthesia during pregnancyT45Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified
Billing statusNon-billable header

Report instead: O29.3X1, O29.3X2, O29.3X3, O29.3X9

Non-billable header

Report instead: T45.0X1A, T45.0X1D, T45.0X1S, T45.0X2A, T45.0X2D

ClassificationO00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A)S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)
DefinitionToxic reaction to local anesthesia during pregnancy is a non-billable ICD-10-CM category code (O29.3).Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified is a non-billable ICD-10-CM category code (T45).
7th characterThe appropriate 7th character is to be added to each code from category T45
Includes
maternal complications arising from the administration of a general, regional or local anesthetic, analgesic or other sedation during pregnancy
adverse effect of correct substance properly administered
poisoning by overdose of substance
poisoning by wrong substance given or taken in error
underdosing by (inadvertently) (deliberately) taking less substance than prescribed or instructed
Use additional code
code, if necessary, to identify the complication
code(s) to specify:
manifestations of poisoning
underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
Code first
, for adverse effects, the nature of the adverse effect, such as:
adverse effect NOS (T88.7)

Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources