2027 ICD-10-CM Diagnosis Code T43Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified
T43 is a non-billable ICD-10-CM category code for poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified, so it cannot be submitted on claims. Use a more specific code from this category instead, such as T43.011A, T43.011D, T43.011S, and T43.012A.
Code Identity
Code Classification
Specific Coding for Psychotropic drugs, not elsewhere classifiedOverview
Non-specific codes like T43 require more characters. Use one of these billable codes instead:
T43.0 for Poisoning by, adverse effect of and underdosing of tricyclic and tetracyclic antidepressants
T43.01 for Poisoning by, adverse effect of and underdosing of tricyclic antidepressants
T43.02 for Poisoning by, adverse effect of and underdosing of tetracyclic antidepressants
T43.1 for Poisoning by, adverse effect of and underdosing of monoamine-oxidase-inhibitor antidepressants
T43.1X for Poisoning by, adverse effect of and underdosing of monoamine-oxidase-inhibitor antidepressants
T43.2 for Poisoning by, adverse effect of and underdosing of other and unspecified antidepressants
T43.20 for Poisoning by, adverse effect of and underdosing of unspecified antidepressants
T43.21 for Poisoning by, adverse effect of and underdosing of selective serotonin and norepinephrine reuptake inhibitors
T43.22 for Poisoning by, adverse effect of and underdosing of selective serotonin reuptake inhibitors
T43.29 for Poisoning by, adverse effect of and underdosing of other antidepressants
T43.3 for Poisoning by, adverse effect of and underdosing of phenothiazine antipsychotics and neuroleptics
T43.3X for Poisoning by, adverse effect of and underdosing of phenothiazine antipsychotics and neuroleptics
T43.4 for Poisoning by, adverse effect of and underdosing of butyrophenone and thiothixene neuroleptics
T43.4X for Poisoning by, adverse effect of and underdosing of butyrophenone and thiothixene neuroleptics
T43.5 for Poisoning by, adverse effect of and underdosing of other and unspecified antipsychotics and neuroleptics
T43.50 for Poisoning by, adverse effect of and underdosing of unspecified antipsychotics and neuroleptics
T43.59 for Poisoning by, adverse effect of and underdosing of other antipsychotics and neuroleptics
T43.6 for Poisoning by, adverse effect of and underdosing of psychostimulants
T43.60 for Poisoning by, adverse effect of and underdosing of unspecified psychostimulant
T43.61 for Poisoning by, adverse effect of and underdosing of caffeine
T43.62 for Poisoning by, adverse effect of and underdosing of amphetamines
T43.63 for Poisoning by, adverse effect of and underdosing of methylphenidate
T43.64 for Poisoning by ecstasy
T43.65 for Poisoning by, adverse effect of and underdosing of methamphetamines
T43.69 for Poisoning by, adverse effect of and underdosing of other psychostimulants
T43.8 for Poisoning by, adverse effect of and underdosing of other psychotropic drugs
T43.8X for Poisoning by, adverse effect of and underdosing of other psychotropic drugs
T43.9 for Poisoning by, adverse effect of and underdosing of unspecified psychotropic drug
T43.91 for Poisoning by unspecified psychotropic drug, accidental (unintentional)
T43.92 for Poisoning by unspecified psychotropic drug, intentional self-harm
T43.93 for Poisoning by unspecified psychotropic drug, assault
T43.94 for Poisoning by unspecified psychotropic drug, undetermined
T43.95 for Adverse effect of unspecified psychotropic drug
T43.96 for Underdosing of unspecified psychotropic drug
Coding GuidelinesGuidance
When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified (T43). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to T43: its own notes plus those printed at block T36-T50 and Chapter 19. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- 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: the excluded code is never reported together with this one, unless the two conditions are unrelated.
- toxic reaction to local anesthesia in pregnancy (O29.3-)
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Code First
The underlying condition named in the note is sequenced before this code.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify any retained foreign body, if applicable (Z18.-)
Notes
General instructions on how these codes are used.
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
7th Character
Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.
- The appropriate 7th character is to be added to each code from category T43
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Patient EducationClinical
Drug Reactions
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Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Code HistoryHistory
Questions About T43Overview
Is T43 a billable code?
No. This is a category header that groups the codes for poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified, and headers cannot be submitted on claims. Claims for poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified need a more specific code from this category, such as T43.011A, T43.011D, and T43.011S.
Can T43 be reported with a code from O29.3?
Not as a rule. The Excludes1 note at block T36-T50, which applies to T43, lists "toxic reaction to local anesthesia in pregnancy (O29.3-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
