ICD-10-CM 2027
ICD-10 code for Lethargy
From the official ICD-10-CM alphabetic index entry “Lethargy”. Page updated September 29, 2026.
About coding Lethargy
The ICD-10-CM code for Lethargy is R53.83 (Other fatigue).
Within R53.8, choose R53.83 (Other fatigue) only when documentation doesn't support a more specific option: other malaise (R53.81) and chronic fatigue, unspecified (R53.82).
The conditions in its Excludes2 note aren't part of R53.83, but may be coded alongside it if the patient has both: exhaustion and fatigue due to depressive episode (F32.-).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about Lethargy ICD-10 codes
What is the ICD-10 code for Lethargy?
- R53.83 — Other fatigue.
Is R53.83 billable?
- Yes. R53.83 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R53.83 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R53.83 as a principal diagnosis.
Is R53.83 a CC or MCC?
- No. R53.83 is neither a CC nor an MCC under MS-DRG v44.0.