Excludes1 pair

K91.0 vs R11-

K91.0 and R11 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 R11
vomiting following gastrointestinal surgery (K91.0)
K91.0

Vomiting following gastrointestinal surgery

Billable
Chapter 11
Diseases of the digestive system
Section
K90-K95
Indexed under
  • Vomiting › following gastrointestinal surgery
  • Vomiting › bilious › following gastro-intestinal surgery
  • Complication › gastrointestinal › postoperative › vomiting after GI surgery
R11

Nausea and vomiting

Not billable
Chapter 18
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
Section
R10-R19

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