Excludes1 pair

E05- vs E06.2

E05 and E06.2 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 E05
chronic thyroiditis with transient thyrotoxicosis (E06.2)
E05

Thyrotoxicosis [hyperthyroidism]

Not billable
Chapter 4
Endocrine, nutritional and metabolic diseases
Section
E00-E07
E06.2

Chronic thyroiditis with transient thyrotoxicosis

Billable
Chapter 4
Endocrine, nutritional and metabolic diseases
Section
E00-E07
Indexed under
  • Thyrotoxicosis › transient with chronic thyroiditis
  • Thyroiditis › chronic › with thyrotoxicosis, transient

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