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T40.491 ICD-10-CM Code: Poisoning by other synthetic narcotics, accidental (unintentional)

Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.

Official Registry Overview & Definition

Poisoning by other synthetic narcotics, accidental (unintentional) is a non-billable ICD-10-CM category code (T40.491). A more specific billable subcode must be selected for claims submission.

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for T40.491 in the official ICD-10-CM tabular list.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • 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

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Poisoning by other synthetic narcotics NOS

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Code First

Underlying conditions that must be sequenced before this code.

  • Code first, for adverse effects, the nature of the adverse effect, such as:
  • adverse effect NOS (T88.7)
  • aspirin gastritis (K29.-)
  • blood disorders (D56-D76)
  • contact dermatitis (L23-L25)
  • dermatitis due to substances taken internally (L27.-)
  • nephropathy (N14.0-N14.2)

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code(s) to specify:
  • manifestations of poisoning
  • underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
  • underdosing of medication regimen (Z91.12-, Z91.13-)

Frequently Compared Codes

The official Excludes notes on T40.491 name these codes. Each comparison page covers when the two can — or must not — be reported together.

Change history

  • FY2021 — 2020-10-01
    Added to the code set
    Poisoning by other synthetic narcotics, accidental (unintentional)
    FY2021 changes

Verify Before Coding

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.

Contextual Map

Every relationship of T40.491 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Hierarchy

  • S00-T88 — Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) (S00-T88) [Hierarchy]
  • T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances [Hierarchy]
  • T40-T41 — Analgesics & Antipyretics [Hierarchy]

Drugs & chemicals (24)

  • Alphaprodine — Alphaprodine — Poisoning, Accidental (unintentional) [Drug table]: “Alphaprodine (Poisoning, Accidental (unintentional))”
  • Anileridine — Anileridine — Poisoning, Accidental (unintentional) [Drug table]: “Anileridine (Poisoning, Accidental (unintentional))”
  • Bezitramide — Bezitramide — Poisoning, Accidental (unintentional) [Drug table]: “Bezitramide (Poisoning, Accidental (unintentional))”
  • Buprenorphine — Buprenorphine — Poisoning, Accidental (unintentional) [Drug table]: “Buprenorphine (Poisoning, Accidental (unintentional))”
  • Butorphanol — Butorphanol — Poisoning, Accidental (unintentional) [Drug table]: “Butorphanol (Poisoning, Accidental (unintentional))”
  • Dextromoramide — Dextromoramide — Poisoning, Accidental (unintentional) [Drug table]: “Dextromoramide (Poisoning, Accidental (unintentional))”
  • Dextropropoxyphene — Dextropropoxyphene — Poisoning, Accidental (unintentional) [Drug table]: “Dextropropoxyphene (Poisoning, Accidental (unintentional))”
  • Dipipanone — Dipipanone — Poisoning, Accidental (unintentional) [Drug table]: “Dipipanone (Poisoning, Accidental (unintentional))”
  • and 16 more

Nearest codes (40)

  • T40 — Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] [Sibling]
  • T40.422A — Poisoning by tramadol, intentional self-harm, initial encounter [Sibling]
  • T40.422D — Poisoning by tramadol, intentional self-harm, subsequent encounter [Sibling]
  • T40.422S — Poisoning by tramadol, intentional self-harm, sequela [Sibling]
  • T40.423 — Poisoning by tramadol, assault [Sibling]
  • T40.423A — Poisoning by tramadol, assault, initial encounter [Sibling]
  • T40.423D — Poisoning by tramadol, assault, subsequent encounter [Sibling]
  • T40.423S — Poisoning by tramadol, assault, sequela [Sibling]
  • and 32 more

Change history

  • FY2021 — Added to the code set [Change history]

Frequently Asked Questions (FAQ) & Clinical Guidance

Can T40.491 be billed directly?

No. T40.491 (Poisoning by other synthetic narcotics, accidental (unintentional)) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does T40.491 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category T40.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to T40.491 in its code family, with their registry titles.

  • T40.426 — Underdosing of tramadol
  • T40.426A — Underdosing of tramadol, initial encounter
  • T40.426D — Underdosing of tramadol, subsequent encounter
  • T40.426S — Underdosing of tramadol, sequela
  • T40.49 — Poisoning by, adverse effect of and underdosing of other synthetic narcotics
  • T40.491A — Poisoning by other synthetic narcotics, accidental (unintentional), initial encounter
  • T40.491D — Poisoning by other synthetic narcotics, accidental (unintentional), subsequent encounter
  • T40.491S — Poisoning by other synthetic narcotics, accidental (unintentional), sequela
  • T40.492 — Poisoning by other synthetic narcotics, intentional self-harm
  • T40.492A — Poisoning by other synthetic narcotics, intentional self-harm, initial encounter

View all codes in the T40 family

Associated Substances (24)

Substances from the official ICD-10-CM Table of Drugs and Chemicals that map to this code.

  • Alphaprodine
  • Anileridine
  • Bezitramide
  • Buprenorphine
  • Butorphanol
  • Dextromoramide
  • Dextropropoxyphene
  • Dipipanone
  • Eptazocine
  • Ethoheptazine
  • Isonipecaine
  • Ketobemidone
  • Levopropoxyphene
  • Levorphanol
  • Meperidine
  • Nalbuphine
  • Pentazocine
  • Pethidine
  • Phenazocine
  • Phenoperidine
  • Piritramide
  • Profadol
  • Propoxyphene
  • Tilidine