ICD-9-CM diagnosis code (retired)
986 — Toxic effect of carbon monoxide
About ICD-9-CM 986
986 is an ICD-9-CM diagnosis code for toxic effect of carbon monoxide. ICD-9-CM was retired for U.S. claims on October 1, 2015, when ICD-10-CM took over.
The CMS General Equivalence Mappings translate it to 20 ICD-10-CM codes, such as T58.01XA (Toxic effect of carbon monoxide from motor vehicle exhaust, accidental (unintentional), initial encounter), T58.02XA (Toxic effect of carbon monoxide from motor vehicle exhaust, intentional self-harm, initial encounter) and T58.03XA (Toxic effect of carbon monoxide from motor vehicle exhaust, assault, initial encounter). All of these are approximate matches, so review the record to pick the right one.
ICD-10-CM equivalents
- T58.01XAToxic effect of carbon monoxide from motor vehicle exhaust, accidental (unintentional), initial encounterapproximate
- T58.02XAToxic effect of carbon monoxide from motor vehicle exhaust, intentional self-harm, initial encounterapproximate
- T58.03XAToxic effect of carbon monoxide from motor vehicle exhaust, assault, initial encounterapproximate
- T58.04XAToxic effect of carbon monoxide from motor vehicle exhaust, undetermined, initial encounterapproximate
- T58.11XAToxic effect of carbon monoxide from utility gas, accidental (unintentional), initial encounterapproximate
- T58.12XAToxic effect of carbon monoxide from utility gas, intentional self-harm, initial encounterapproximate
- T58.13XAToxic effect of carbon monoxide from utility gas, assault, initial encounterapproximate
- T58.14XAToxic effect of carbon monoxide from utility gas, undetermined, initial encounterapproximate
- T58.2X1AToxic effect of carbon monoxide from incomplete combustion of other domestic fuels, accidental (unintentional), initial encounterapproximate
- T58.2X2AToxic effect of carbon monoxide from incomplete combustion of other domestic fuels, intentional self-harm, initial encounterapproximate
- T58.2X3AToxic effect of carbon monoxide from incomplete combustion of other domestic fuels, assault, initial encounterapproximate
- T58.2X4AToxic effect of carbon monoxide from incomplete combustion of other domestic fuels, undetermined, initial encounterapproximate
- T58.8X1AToxic effect of carbon monoxide from other source, accidental (unintentional), initial encounterapproximate
- T58.8X2AToxic effect of carbon monoxide from other source, intentional self-harm, initial encounterapproximate
- T58.8X3AToxic effect of carbon monoxide from other source, assault, initial encounterapproximate
- T58.8X4AToxic effect of carbon monoxide from other source, undetermined, initial encounterapproximate
- T58.91XAToxic effect of carbon monoxide from unspecified source, accidental (unintentional), initial encounterapproximate
- T58.92XAToxic effect of carbon monoxide from unspecified source, intentional self-harm, initial encounterapproximate
- T58.93XAToxic effect of carbon monoxide from unspecified source, assault, initial encounterapproximate
- T58.94XAToxic effect of carbon monoxide from unspecified source, undetermined, initial encounterapproximate
Common questions about 986
GEMs are a translation aid, not a substitute for coding from the record. The 2027 ICD-10 code set has changed since the last GEMs release in 2018. Page updated September 29, 2026.