F51.1 – Hypersomnia not due to a substance or known physiological condition
ICD-10-CM 2027 diagnosis code · Behavioral syndromes associated with physiological disturbances and physical factors
- Code
F51.1(claims format:F511)- Description
- Hypersomnia not due to a substance or known physiological condition
- Short description
- Hypersomnia not due to a substance or known physiol cond
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 5. Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
- Block
- F50-F59 Behavioral syndromes associated with physiological disturbances and physical factors
- Parent codes
- F51
Billable codes under F51.1
F51.1 is a header code and cannot be used on claims. Choose the most specific code:
Notes for F51.1
- alcohol related hypersomnia (F10.182, F10.282, F10.982)
- drug-related hypersomnia (F11.182, F11.282, F11.982, F13.182, F13.282, F13.982, F14.182, F14.282, F14.982, F15.182, F15.282, F15.982, F19.182, F19.282, F19.982)
- hypersomnia NOS (G47.10)
- hypersomnia due to known physiological condition (G47.10)
- idiopathic hypersomnia (G47.11, G47.12)
- narcolepsy (G47.4-)
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
F51 – Sleep disorders not due to a substance or known physiological condition
- organic sleep disorders (G47.-)
Related codes in F51
- F51.0 – Insomnia not due to a substance or known physiological conditionHeader
- F51.3 – Sleepwalking [somnambulism]Billable
- F51.4 – Sleep terrors [night terrors]Billable
- F51.5 – Nightmare disorderBillable
- F51.8 – Other sleep disorders not due to a substance or known physiological conditionBillable
- F51.9 – Sleep disorder not due to a substance or known physiological condition, unspecifiedBillable
Frequently asked questions
What is ICD-10 code F51.1?
F51.1 is the ICD-10-CM code for hypersomnia not due to a substance or known physiological condition, in the block F50-F59 (Behavioral syndromes associated with physiological disturbances and physical factors).
Is F51.1 a billable code?
No. F51.1 is a header code with more specific child codes; report one of the billable codes listed above.
What category does F51.1 belong to?
It belongs to category F51 – Sleep disorders not due to a substance or known physiological condition.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.