ICD-10 Code F18.921 – Inhalant use, unspecified with intoxication with delirium (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F18.921 – Inhalant use, unspecified with intoxication with delirium
What it is
Use F18.921 when the patient has inhalant use, but the specific substance is not documented, and the intoxication includes delirium. This code indicates an acute mental status disturbance related to inhalant exposure.
Clinical signs
Clinical features vary; refer to documentation. Delirium may include confusion, reduced awareness, disorganized thinking, and fluctuating attention during or soon after inhalant use.
When to use this code
Use this code when the record clearly states inhalant intoxication with delirium and does not identify a more specific inhalant. It also fits when the provider documents inhalant-related delirium without further detail. Check documentation if the type of inhalant or the presence of delirium is unclear.
Do not use for
Do not use F18.921 if the note describes inhalant use without delirium, or if a different substance is named. If intoxication is absent, or the mental status change has another cause, choose a different code.
Coding tip
Verify both elements in the chart: unspecified inhalant use and intoxication with delirium.