O29.3 vs T40.906D
O29.3 (Toxic reaction to local anesthesia during pregnancy) compared with T40.906D (Underdosing of unspecified psychodysleptics [hallucinogens], subsequent encounter), 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. T40.906D 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 pregnancy | T40.906DUnderdosing of unspecified psychodysleptics [hallucinogens], subsequent encounter | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | O00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Toxic reaction to local anesthesia during pregnancy is a non-billable ICD-10-CM category code (O29.3). | Underdosing of unspecified psychodysleptics [hallucinogens], subsequent encounter is a billable ICD-10-CM diagnosis code (T40.906D). |
| 7th character | — | The appropriate 7th character is to be added to each code from category T40 |
| 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