F05 – Delirium due to known physiological condition
ICD-10-CM 2027 diagnosis code · Mental disorders due to known physiological conditions
ICD-10-CM code
F05
- Code
F05(claims format:F05)- Description
- Delirium due to known physiological condition
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 5. Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
- Block
- F01-F09 Mental disorders due to known physiological conditions
Notes for F05
Applicable to:
- Acute or subacute brain syndrome
- Acute or subacute confusional state (nonalcoholic)
- Acute or subacute infective psychosis
- Acute or subacute organic reaction
- Acute or subacute psycho-organic syndrome
- Delirium of mixed etiology
- Delirium superimposed on dementia
- Sundowning
Excludes1 (not coded here):
- delirium NOS (R41.0)
Code first:
- the underlying physiological condition, such as:
- dementia (F03.9-)
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
Block F01-F09
Notes:
- This block comprises a range of mental disorders grouped together on the basis of their having in common a demonstrable etiology in cerebral disease, brain injury, or other insult leading to cerebral dysfunction. The dysfunction may be primary, as in diseases, injuries, and insults that affect the brain directly and selectively; or secondary, as in systemic diseases and disorders that attack the brain only as one of the multiple organs or systems of the body that are involved.
Index terms for F05
Entries in the ICD-10-CM alphabetic index that lead to this code:
- Sundowning
- Twilight state, epileptic
- State, twilight, epileptic
- State, confusional, epileptic
- Confusion, confused, epileptic
- Delirium, delirious, puerperal
- Psychosis, psychotic, infective
- Delirium, delirious, postprocedural
- Delirium, delirious, with, dementia
- Puerperal, puerperium, delirium NEC
- Dementia, with, acute confusional state
- Epilepsy, epileptic, epilepsia, twilight
- Confusion, confused, acute, with dementia
- Syndrome, psycho-organic, acute or subacute
- Senile, senility, with, acute confusional state
- Delirium, delirious, due to, multiple etiologies
- Insanity, insane, confusional, acute or subacute
- Psychosis, psychotic, confusional, acute or subacute
- State, confusional, acute, with, senility or dementia
- Delirium, delirious, due to, general medical condition
- Psychosis, psychotic, organic, infective, acute or subacute
- Psychosis, psychotic, organic, post-traumatic, acute or subacute
- Psychosis, psychotic, organic, due to or associated with, epilepsy transient
- Psychosis, psychotic, organic, due to or associated with, trauma, brain, acute or subacute
- Psychosis, psychotic, organic, due to or associated with, infection, brain, acute or subacute
Frequently asked questions
What is ICD-10 code F05?
F05 is the ICD-10-CM code for delirium due to known physiological condition, in the block F01-F09 (Mental disorders due to known physiological conditions).
Is F05 a billable code?
Yes. F05 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.