T42.0X2A is the authoritative medical code for Poisoning by hydantoin derivatives, intentional self-harm, initial encounter. This classification is used in medical billing and clinical recording to specify the clinical criteria for poisoning by hydantoin derivatives, intentional self-harm, initial encounter (ICD-10-CM T42.0X2A), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Poisoning by hydantoin derivatives, intentional self-harm, initial encounter is a billable ICD-10-CM diagnosis code T42.0X2A. Includes: 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. Excludes1 (not coded here): toxic reaction to local anesthesia in pregnancy O29.3-. Excludes2 (not included here): drug dependence and related mental and behavioral disorders due to psychoactive substance use F10.--F19.-; abuse and dependence of psychoactive substances F10-F19; abuse of non-dependence-producing substances F55.-; immunodeficiency due to drugs D84.821; drug reaction and poisoning affecting newborn P00-P96; pathological drug intoxication inebriation F10-F19. 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: 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-). 7th character: The appropriate 7th character is to be added to each code from category T42.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for T42.0X2A 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
Excludes1 — Not Coded Here
Conditions that can never be reported with this code; the two are mutually exclusive.
- toxic reaction to local anesthesia in pregnancy O29.3-
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- drug dependence and related mental and behavioral disorders due to psychoactive substance use F10.--F19.-
- abuse and dependence of psychoactive substances F10-F19
- abuse of non-dependence-producing substances F55.-
- immunodeficiency due to drugs D84.821
- drug reaction and poisoning affecting newborn P00-P96
- pathological drug intoxication inebriation F10-F19
Code First
Underlying conditions that must be sequenced before this code.
- , 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.
- 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 Asked Questions (FAQ) & Clinical Guidance
Does T42.0X2A require a 7th character?
Yes. The appropriate 7th character is to be added to each code from category T42.
What can't be coded together with T42.0X2A?
Per official ICD-10-CM Excludes1 instructions, T42.0X2A must not be reported together with: toxic reaction to local anesthesia in pregnancy (O29.3-).
Can T42.0X2A be reported alongside related conditions?
Per official ICD-10-CM Excludes2 instructions, T42.0X2A and the following are not considered part of each other and may both be reported when both conditions are present: drug dependence and related mental and behavioral disorders due to psychoactive substance use (F10.--F19.-); abuse and dependence of psychoactive substances (F10-F19); abuse of non-dependence-producing substances (F55.-); immunodeficiency due to drugs (D84.821).
Does T42.0X2A need to be sequenced after another code?
Yes. 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).
Is an additional code needed with T42.0X2A?
Use additional code(s) to specify: 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-).
Nearest Codes in This Family
Official ICD-10-CM classifications closest to T42.0X2A in its code family, with their registry titles.
- T42 — Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
- T42-T43 — Anticonvulsants & Psychotropics (T42-T43)
- T42.0 — Poisoning by, adverse effect of and underdosing of hydantoin derivatives
- T42.0X — Poisoning by, adverse effect of and underdosing of hydantoin derivatives
- T42.0X1 — Poisoning by hydantoin derivatives, accidental (unintentional)
- T42.0X1A — Poisoning by hydantoin derivatives, accidental (unintentional), initial encounter
- T42.0X1D — Poisoning by hydantoin derivatives, accidental (unintentional), subsequent encounter
- T42.0X1S — Poisoning by hydantoin derivatives, accidental (unintentional), sequela
- T42.0X2 — Poisoning by hydantoin derivatives, intentional self-harm
- T42.0X2D — Poisoning by hydantoin derivatives, intentional self-harm, subsequent encounter
View all 40 codes in the T42 family
Associated Substances (12)
Substances from the official ICD-10-CM Table of Drugs and Chemicals that map to this code.
- Albutoin
- Dilantin
- Diphenylhydantoin
- Epanutin
- Ethotoin
- Hydantoin derivative NEC
- Mephenytoin
- Metetoin
- Methetoin
- Methoin
- Phenantoin
- Phenytoin