I.C.19.e

Adverse Effects, Poisoning, Underdosing and Toxic Effects

Codes in categories T36-T65 are combination codes that include the substance that was taken as well as the intent. No additional external cause code is required for poisonings, toxic effects, adverse effects and underdosing codes.

In this section

I.C.19.e.1)Do not code directly from the Table of Drugs
I.C.19.e.2)Use as many codes as necessary to describe
I.C.19.e.3)If the same code would describe the causative agent
I.C.19.e.4)If two or more drugs, medicinal or biological substances
I.C.19.e.5)The occurrence of drug toxicity is classified in ICD-10-CM as follows:

ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026 (effective October 1, 2025). Published by CMS and NCHS. Reproduced for reference — always verify against the official CMS release.