ICD-10 Code F16.91 – Hallucinogen use, unspecified, in remission (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F16.91 – Hallucinogen use, unspecified, in remission
What it is
This code identifies a history of hallucinogen use disorder that is now in remission. It means the patient previously met criteria for problematic hallucinogen use, but current active use or active disorder is not documented.
Clinical signs
Clinical features vary; refer to documentation. In remission, you may see no current intoxication, withdrawal, or ongoing behavioral signs, while the record may still note past hallucinogen-related impairment.
When to use this code
Use this code when the provider documents hallucinogen use disorder as being in remission and does not specify a more precise substance. It is appropriate for follow-up visits, problem lists, or histories that still require coding of the disorder. If the chart shows current use, code the active condition instead.
Do not use for
Do not use this code for acute intoxication, withdrawal, or an unspecified hallucinogen-related disorder without remission. Check documentation if the record only mentions past use without a diagnosed use disorder.
Coding tip
Code the remission status only when the provider clearly documents it; otherwise, check documentation.