ICD-10-CM > S00-T88 > T36-T50 > T43 > T43.0 > T43.02 > T43.021 T43.021 Poisoning by tetracyclic antidepressants, accidental (unintentional) Non-Billable/Non-Specific Applicable To Poisoning by tetracyclic antidepressants NOS Codes T43.021A..., initial encounterT43.021D..., subsequent encounterT43.021S..., sequela