ICD-10-CM · Chapter 5 · F01–F99
F51.1
Hypersomnia not due to a substance or known physiological condition
Mental, behavioral and neurodevelopmental disorders
Heads up:this is a parent code. It's typically not directly billable — you need to drill down to a more specific child code (one with additional digits) to use on a claim.
Quick facts
- Code
- F51.1
- Type
- Category / header (non-billable)
- ICD-10-CM chapter
- Chapter 5 — Mental, behavioral and neurodevelopmental disorders
- Category
- F51 — Sleep disorders not due to a substance or known physiological condition
- Specificity
- 4 characters
How coders use this code
ICD-10-CM F51.1 is a category (header) for hypersomnia not due to a substance or known physiological condition. It is generally not reported directly on a claim — coders drill down to a more specific child code (one with additional characters) that matches the documentation. Use the related codes below to find the billable code that fits, and verify against the annual NCHS/CMS guidelines.
Related codes in F51
- F51Sleep disorders not due to a substance or known physiological condition
- F51.0Insomnia not due to a substance or known physiological condition
- F51.01Primary insomnia
- F51.02Adjustment insomnia
- F51.03Paradoxical insomnia
- F51.04Psychophysiologic insomnia
- F51.05Insomnia due to other mental disorder
- F51.09Other insomnia not due to a substance or known physiological condition
- F51.11Primary hypersomnia
- F51.12Insufficient sleep syndrome
- F51.13Hypersomnia due to other mental disorder
- F51.19Other hypersomnia not due to a substance or known physiological condition
- F51.3Sleepwalking [somnambulism]
- F51.4Sleep terrors [night terrors]
- F51.5Nightmare disorder
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