ICD-10-CM 2027
ICD-10 code for idiopathic hypersomnia
From the official ICD-10-CM alphabetic index entry “Hypersomnia (organic) › idiopathic”. Page updated September 29, 2026.
About coding idiopathic hypersomnia
The ICD-10-CM code for idiopathic hypersomnia is G47.11 (Idiopathic hypersomnia with long sleep time). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on G47.11.
Within G47.1 (hypersomnia), G47.11 is specifically for idiopathic hypersomnia with long sleep time. Related codes cover unspecified (G47.10), idiopathic hypersomnia without long sleep time (G47.12), recurrent hypersomnia (G47.13), due to medical condition (G47.14) and other hypersomnia (G47.19).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 887 (Other Mental Disorder Diagnoses, relative weight 1.1139), in MDC 19 (Mental Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific idiopathic hypersomnia codes (official index)
Common questions about idiopathic hypersomnia ICD-10 codes
What is the ICD-10 code for idiopathic hypersomnia?
- G47.11 — Idiopathic hypersomnia with long sleep time. More specific codes apply when the documentation supports them: G47.11, G47.12.
Is G47.11 billable?
- Yes. G47.11 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G47.11 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G47.11 as a principal diagnosis.
Is G47.11 a CC or MCC?
- No. G47.11 is neither a CC nor an MCC under MS-DRG v44.0.