F05

Billable
ChapterF01–F99
Rankcategory
Official Description

Delirium due to known physiological condition

Metadata & Insights
  • •2026 ICD-10-CM Edition - Effective October 1, 2025.
  • •Billable/specific code (valid for reimbursement).
  • •Chapter 5: Mental, Behavioral and Neurodevelopmental Disorders (F01-F99).

CH5 Parent Instructions

Includes
  • disorders of psychological development
Excludes2(Not included here)
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)

Instructional Notes

Includes
  • 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)
Excludes2(Not included here)
Code First
  • the underlying physiological condition, such as:
  • dementia (F03.9-)

Clinical Hierarchy

CH5Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
F01-F09Mental disorders due to known physiological conditions (F01-F09)
F05Delirium due to known physiological condition

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to F05:

chapterCH5
Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
View context instructions

Alphabetic Index Mentions

These are Diagnosis Index lookup paths that route to F05. Use them as entry terms for search, then confirm final coding instructions in the Tabular List and notes above.

25 raw paths
Confusion, confused1 unique routes
epileptic→F05
Delirium, delirious (acute or subacute) (not alcohol- or drug-induced)5 unique routes
due to (secondary to)(2 variants)
general medical condition→F05
multiple etiologies→F05
postprocedural (postoperative)→F05
puerperal→F05
with
dementia→F05
Dementia (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)1 unique routes
with
acute confusional state→F05
Epilepsy, epileptic, epilepsia (attack) (cerebral) (convulsion) (fit) (seizure)1 unique routes
twilight→F05
Insanity, insane1 unique routes
confusional
acute or subacute→F05
Psychosis, psychotic8 unique routes
confusional
acute or subacute→F05
infective (acute) (subacute)→F05
organic(6 variants)
due to or associated with(4 variants)
disease
endocrine or metabolic
acute or subacute→F05
epilepsy transient (acute)→F05
infection
brain (intracranial)
acute or subacute→F05
trauma, brain (birth) (from electric current) (surgical)
acute or subacute→F05
infective
acute or subacute→F05
post-traumatic
acute or subacute→F05
Puerperal, puerperium (complicated by, complications)1 unique routes
delirium NEC→F05
Senile, senility1 unique routes
with
acute confusional state→F05
State (of)3 unique routes
confusional (psychogenic)(2 variants)
acute
with
senility or dementia→F05
epileptic→F05
twilight
epileptic→F05
Sundowning1 unique routes
Direct index entry→F05
Syndrome1 unique routes
psycho-organic (nonpsychotic severity)
acute or subacute→F05
Twilight state1 unique routes
epileptic→F05

MS-DRG Classification

2026 v43.1

This code is grouped within the following Diagnosis Related Group(s) for clinical reimbursement:

DRG 880
Acute Adjustment Reaction and Psychosocial Dysfunction

Cross Reference

Find Procedures (ICD-10-PCS)

Find surgical and procedural codes related to Delirium due to known physiological condition.

Search PCS Codes