Excludes1 pair

F04 vs R41.1

F04 and R41.1 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on F04
anterograde amnesia (R41.1)
F04

Amnestic disorder due to known physiological condition

Billable
Chapter 5
Mental, Behavioral and Neurodevelopmental disorders
Section
F01-F09
Use when the record says
  • Korsakov's psychosis or syndrome, nonalcoholic
Indexed under
  • Amnes (t)ic syndrome (post-traumatic)
  • Meynert's amentia (nonalcoholic)
  • Toxemica cerebropathia psychica (nonalcoholic)
  • Amentia › Meynert's (nonalcoholic)
  • Disease, diseased › Korsakoff's (nonalcoholic)
R41.1

Anterograde amnesia

Billable
Chapter 18
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
Section
R40-R46
Indexed under
  • Amnesia › anterograde

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027