2026 ICD-10-CM Diagnosis Code T37Poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics
T37 is a non-billable ICD-10-CM category code for poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics, so it cannot be submitted on claims. Use a more specific code from this category instead, such as T37.0X1A, T37.0X1D, T37.0X1S, and T37.0X2A.
Code Identity
Code Classification
Specific Coding for Other systemic anti-infectives and antiparasiticsOverview
Non-specific codes like T37 require more characters. Use one of these billable codes instead:
T37.0 for Poisoning by, adverse effect of and underdosing of sulfonamides
T37.0X for Poisoning by, adverse effect of and underdosing of sulfonamides
T37.1 for Poisoning by, adverse effect of and underdosing of antimycobacterial drugs
T37.1X for Poisoning by, adverse effect of and underdosing of antimycobacterial drugs
T37.2 for Poisoning by, adverse effect of and underdosing of antimalarials and drugs acting on other blood protozoa
T37.2X for Poisoning by, adverse effect of and underdosing of antimalarials and drugs acting on other blood protozoa
T37.3 for Poisoning by, adverse effect of and underdosing of other antiprotozoal drugs
T37.3X for Poisoning by, adverse effect of and underdosing of other antiprotozoal drugs
T37.4 for Poisoning by, adverse effect of and underdosing of anthelminthics
T37.4X for Poisoning by, adverse effect of and underdosing of anthelminthics
T37.5 for Poisoning by, adverse effect of and underdosing of antiviral drugs
T37.5X for Poisoning by, adverse effect of and underdosing of antiviral drugs
T37.8 for Poisoning by, adverse effect of and underdosing of other specified systemic anti-infectives and antiparasitics
T37.8X for Poisoning by, adverse effect of and underdosing of other specified systemic anti-infectives and antiparasitics
T37.9 for Poisoning by, adverse effect of and underdosing of unspecified systemic anti-infective and antiparasitics
T37.91 for Poisoning by unspecified systemic anti-infective and antiparasitics, accidental (unintentional)
T37.92 for Poisoning by unspecified systemic anti-infective and antiparasitics, intentional self-harm
T37.93 for Poisoning by unspecified systemic anti-infective and antiparasitics, assault
T37.94 for Poisoning by unspecified systemic anti-infective and antiparasitics, undetermined
T37.95 for Adverse effect of unspecified systemic anti-infective and antiparasitic
T37.96 for Underdosing of unspecified systemic anti-infectives and antiparasitics
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 other systemic anti-infectives and antiparasitics (T37). 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 2026, published by CMS and the National Center for Health Statistics.
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
- anti-infectives topically used for ear, nose and throat T49.6
- anti-infectives topically used for eye T49.5
- locally applied anti-infectives NEC T49.0
7th Character Note
- The appropriate 7th character is to be added to each code from category T37
7th Character
- A - initial encounter
- D - subsequent encounter
- S - sequela
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.
Indicates that a seventh character is to be assigned to codes in a subcategory.
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Code HistoryHistory
Questions About T37Overview
Is T37 a billable code?
No. This is a category header that groups the codes for poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics, and headers cannot be submitted on claims. Claims for poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics need a more specific code from this category, such as T37.0X1A, T37.0X1D, and T37.0X1S.
