ICD-10 Code T40.4X4

Poisoning by other synthetic narcotics, undetermined

Version 2019 Replaced Code Non-Billable Code Poisoning Undetermined

Not Valid for Submission

T40.4X4 is a "header" nonspecific and non-billable code code, consider using a code with a higher level of specificity for a diagnosis of poisoning by other synthetic narcotics, undetermined. The code is NOT valid for the year 2020 for the submission of HIPAA-covered transactions.

ICD-10: T40.4X4
Short Description:Poisoning by other synthetic narcotics, undetermined
Long Description:Poisoning by other synthetic narcotics, undetermined

Consider the following ICD-10 codes with a higher level of specificity:

  • T40.4X4A - Poisoning by other synthetic narcotics, undetermined, initial encounter
  • T40.4X4D - Poisoning by other synthetic narcotics, undetermined, subsequent encounter
  • T40.4X4S - Poisoning by other synthetic narcotics, undetermined, sequela

Replaced Code

This code was replaced in the 2020 ICD-10 code set with the code(s) listed below. The National Center for Health Statistics (NCHS) has published an update to the ICD-10-CM diagnosis codes which became effective October 1, 2019. This code was replaced for the FY 2020 (October 1, 2019 - September 30, 2020).

  • K59.03 - Drug induced constipation

Code Classification

  • Injury, poisoning and certain other consequences of external causes (S00–T98)
    • Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances (T36-T50)
      • Narcotics and psychodysleptics (T40)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (first year ICD-10-CM implemented into the HIPAA mandated code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Medical Professionals


The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acetaminophen and dextropropoxyphene overdose
  • Acetaminophen and dextropropoxyphene overdose of undetermined intent
  • Acetaminophen and dextropropoxyphene poisoning
  • Acetaminophen and dextropropoxyphene poisoning of undetermined intent
  • Acetaminophen overdose
  • Acetaminophen overdose
  • Acetaminophen overdose of undetermined intent
  • Acetaminophen poisoning of undetermined intent
  • Alfentanil overdose
  • Alfentanil overdose of undetermined intent
  • Alfentanil poisoning
  • Alfentanil poisoning of undetermined intent
  • Buprenorphine overdose
  • Buprenorphine overdose of undetermined intent
  • Buprenorphine poisoning
  • Buprenorphine poisoning of undetermined intent
  • Dextromoramide overdose
  • Dextromoramide overdose of undetermined intent
  • Dextromoramide poisoning
  • Dextromoramide poisoning of undetermined intent
  • Dextropropoxyphene overdose
  • Dextropropoxyphene overdose
  • Dextropropoxyphene overdose of undetermined intent
  • Dextropropoxyphene overdose of undetermined intent
  • Dextropropoxyphene poisoning
  • Dextropropoxyphene poisoning
  • Dextropropoxyphene poisoning of undetermined intent
  • Dextropropoxyphene poisoning of undetermined intent
  • Dipipanone overdose
  • Dipipanone overdose of undetermined intent
  • Dipipanone poisoning
  • Dipipanone poisoning of undetermined intent
  • Fentanyl overdose
  • Fentanyl overdose of undetermined intent
  • Fentanyl poisoning
  • Fentanyl poisoning of undetermined intent
  • Levorphanol overdose
  • Levorphanol overdose of undetermined intent
  • Levorphanol poisoning
  • Levorphanol poisoning of undetermined intent
  • Methadone analog poisoning
  • Methadone analog poisoning
  • Morphinan opioid poisoning
  • Morphinan opioid poisoning
  • Nalbuphine overdose
  • Nalbuphine overdose of undetermined intent
  • Nalbuphine poisoning
  • Nalbuphine poisoning of undetermined intent
  • Pentazocine overdose
  • Pentazocine overdose of undetermined intent
  • Pentazocine poisoning of undetermined intent
  • Pethidine overdose
  • Pethidine overdose of undetermined intent
  • Pethidine poisoning of undetermined intent
  • Phenazocine overdose
  • Phenazocine overdose of undetermined intent
  • Phenazocine poisoning
  • Phenazocine poisoning of undetermined intent
  • Phenoperidine overdose
  • Phenoperidine overdose of undetermined intent
  • Phenoperidine poisoning
  • Phenoperidine poisoning of undetermined intent
  • Poisoning by meperidine
  • Poisoning by pentazocine
  • Poisoning caused by acetaminophen

Table of Drugs and Chemicals

The code T40.4X4 is included in the Table of Drugs and Chemicals, this table contains a classification of drugs, industrial solvents, corrosive gases, noxious plants, pesticides, and other toxic agents. Each substance in the table is assigned a code according to the poisoning classification and external causes of adverse effects. Use as many codes as necessary to describe all reported drugs, medicinal or chemical substances.

Substance Poisoning

Information for Patients


A poison is any substance that is harmful to your body. You might swallow it, inhale it, inject it, or absorb it through your skin. Any substance can be poisonous if too much is taken. Poisons can include

  • Prescription or over-the-counter medicines taken in doses that are too high
  • Overdoses of illegal drugs
  • Carbon monoxide from gas appliances
  • Household products, such as laundry powder or furniture polish
  • Pesticides
  • Indoor or outdoor plants
  • Metals such as lead and mercury

The effects of poisoning range from short-term illness to brain damage, coma, and death. To prevent poisoning it is important to use and store products exactly as their labels say. Keep dangerous products where children can't get to them. Treatment for poisoning depends on the type of poison. If you suspect someone has been poisoned, call your local poison control center at 1-800-222-1222 right away.

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ICD-10 Footnotes

General Equivalence Map Definitions
The ICD-10 and ICD-9 GEMs are used to facilitate linking between the diagnosis codes in ICD-9-CM and the new ICD-10-CM code set. The GEMs are the raw material from which providers, health information vendors and payers can derive specific applied mappings to meet their needs.

  • Approximate Flag - The approximate flag is on, indicating that the relationship between the code in the source system and the code in the target system is an approximate equivalent.
  • No Map Flag - The no map flag indicates that a code in the source system is not linked to any code in the target system.
  • Combination Flag - The combination flag indicates that more than one code in the target system is required to satisfy the full equivalent meaning of a code in the source system.