F09 Unspecified mental disorder due to known physiological condition

Billable ICD-10-CM code, FY2026.

Applicable to

• Mental disorder NOS due to known physiological condition
• Organic brain syndrome NOS
• Organic mental disorder NOS
• Organic psychosis NOS
• Symptomatic psychosis NOS

Excludes1 (never code together)

• mild neurocognitive disorder due to known physiological condition (F06.7-)
• psychosis NOS (F29)

Code first

• the underlying physiological condition

Applies from F09 Unspecified mental disorder due to known physiological condition

Applicable to

• Mental disorder NOS due to known physiological condition
• Organic brain syndrome NOS
• Organic mental disorder NOS
• Organic psychosis NOS
• Symptomatic psychosis NOS

Excludes1 (never code together)

• mild neurocognitive disorder due to known physiological condition (F06.7-)
• psychosis NOS (F29)

Code first

• the underlying physiological condition

MS-DRG index

Defines the logic of DRG(s) 884 in MDC 19.

Approximate ICD-9-CM (GEMs)

• 310.9 Unspecified nonpsychotic mental disorder following organic brain damage (approximate)

Code annotations containing back-references to F09

Back-references to F09

• Type 1 Excludes: F29 Unspecified psychosis not due to a substance or known physiological condition ("unspecified mental disorder due to known physiological condition (F09)")
• Type 2 Excludes: F63.1 Pyromania ("mental disorders due to known physiological condition (F01-F09)")
• Type 2 Excludes: F63.2 Kleptomania ("stealing in mental disorders due to known physiological condition (F01-F09)")
• Type 1 Excludes: F99 Mental disorder, not otherwise specified ("unspecified mental disorder due to known physiological condition (F09)")

Back-references to F09

• Type 1 Excludes: F29 Unspecified psychosis not due to a substance or known physiological condition ("unspecified mental disorder due to known physiological condition (F09)")
• Type 2 Excludes: F63.1 Pyromania ("mental disorders due to known physiological condition (F01-F09)")
• Type 2 Excludes: F63.2 Kleptomania ("stealing in mental disorders due to known physiological condition (F01-F09)")
• Type 1 Excludes: F99 Mental disorder, not otherwise specified ("unspecified mental disorder due to known physiological condition (F09)")

Diagnosis Index entries for F09

• Deficiency, deficient › cognitive
• Disease, diseased › mental › organic
• Disorder (of) › cognitive
• Disorder (of) › cognitive › due to (secondary to) general medical condition
• Disorder (of) › mental (or behavioral) (nonpsychotic) › due to (secondary to) › brain disease, damage and dysfunction
• Disorder (of) › mental (or behavioral) (nonpsychotic) › due to (secondary to) › general medical condition
• Disorder (of) › mental (or behavioral) (nonpsychotic) › organic or symptomatic
• Organic › brain syndrome
• Organic › mental disorder
• Organic › psychosis
• Psychosis, psychotic › organic
• Psychosis, psychotic › symptomatic
• Syndrome › brain (nonpsychotic)
• Syndrome › brain (nonpsychotic) › with psychosis, psychotic reaction
• Syndrome › brain (nonpsychotic) › organic
• Syndrome › brain (nonpsychotic) › organic › post-traumatic (nonpsychotic) › psychotic
• Syndrome › brain (nonpsychotic) › psycho-organic
• Syndrome › organic › brain

Nearby codes

• F09 Unspecified mental disorder due to known physiological condition (this code)