ICD-10-CM > S00-T88 > T36-T50 > T40 > T40.3 > T40.3X > T40.3X1 T40.3X1 Poisoning by methadone, accidental (unintentional) Non-Billable/Non-Specific Applicable To Poisoning by methadone NOS Codes T40.3X1A..., initial encounterT40.3X1D..., subsequent encounterT40.3X1S..., sequela