ICD-10 Code F18.121 – Inhalant abuse with intoxication delirium (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F18.121 – Inhalant abuse with intoxication delirium
What it is
F18.121 identifies inhalant abuse accompanied by delirium caused by intoxication. Use it when inhaled substances are being misused and the patient shows an acute confusional state linked to intoxication.
Clinical signs
Clinical features may include disturbed attention, disorientation, impaired awareness, and fluctuating mental status. Clinical features vary; refer to documentation for evidence that delirium is due to inhalant intoxication.
When to use this code
Use this code when the record clearly documents inhalant abuse and delirium from intoxication, not just simple intoxication or substance use. The note should connect the delirium to the inhalant exposure. Check documentation if the provider only describes confusion without specifying delirium.
Do not use for
Do not use F18.121 for inhalant use without abuse, or for intoxication without delirium. Do not assign it when delirium has another documented cause.
Coding tip
Verify that both inhalant abuse and intoxication delirium are documented together before reporting F18.121.