Is ICD-10-CM code T59 billable?

No, T59 (Toxic effect of other gases, fumes and vapors) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code T59 belong to?

T59 belongs to Chapter 19 of the ICD-10-CM tabular list: S00–T88 (Injury, Poisoning and Certain Other Consequences of External Causes).

T59Not billable, use a more specific code below

Toxic effect of other gases, fumes and vapors

In Toxic effects of substances chiefly nonmedicinal as to source (T51-T65), chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes

144 billable codes under T59: none are a CC or MCC; 11 map to HCC 155 (Major Depression, Moderate or Severe, without Psychosis).An HCC counts toward a Medicare Advantage patient's risk score.

Instructional notes

Includes: conditions that are coded here

aerosol propellants

Excludes1: not coded here, use a different code

chlorofluorocarbons (T53.5)

Also applies, from Toxic effects of substances chiefly nonmedicinal as to source (T51-T65)

These notes sit on T51-T65 and apply to every code under it, including T59.

Excludes1: not coded here, use a different code

contact with and (suspected) exposure to toxic substances (Z77.-)

Use additional code: add a second code for this, listed after this one

code(s):
for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70)
personal history of foreign body fully removed (Z87.821)
to identify any retained foreign body, if applicable (Z18.-)

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Section I.C.19.e Adverse Effects, Poisoning, Underdosing and Toxic Effects (page 82), covers T59
For adverse effects, code the effect first, then T36-T50 with character 5. Sequence poisonings (unknown intent coded accidental) and toxic effects (T51-T65) first; underdosing (character 6) is never first-listed.

All codes under T59

T59 can't be used on a claim. Pick a billable code below; grey headings group them.

T59 MS-DRGs

As the principal diagnosis, the billable codes under T59 group to MS-DRG 917, 918, 922, 923, 949, or 950 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

DRG 917 Poisoning and Toxic Effects of Drugs with MCC (48 of 144 codes)
DRG 918 Poisoning and Toxic Effects of Drugs without MCC (48 of 144 codes)
DRG 922 Other Injury, Poisoning and Toxic Effect Diagnoses with MCC (48 of 144 codes)
DRG 923 Other Injury, Poisoning and Toxic Effect Diagnoses without MCC (48 of 144 codes)
DRG 949 Aftercare with CC/MCC (48 of 144 codes)
DRG 950 Aftercare without CC/MCC (48 of 144 codes)

Other codes that refer to T59

Notes on these codes point to T59.

T71 Excludes1: asphyxia from other gases, fumes and vapors (T59.-)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Poisoning

A poison is any substance that is harmful to your body. You might swallow it, inhale it, inject it, or absorb it through your skin. Any substance can be poisonous if too much is taken. Poisons can include:

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.