F51.1 Hypersomnia not due to a substance or known physiological condition

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Hypersomnia not due to a substance or known physiological condition is F51.1 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
F50-F59: Behavioral syndromes associated with physiological disturbances and physical factors (F50-F59)
Category F51
18 codes (15 billable)
FY2026 Status
Stable since FY2024
Excludes2
Not included here. These conditions are coded elsewhere but may be coded together if applicable.
  • 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-)

Official Coding Guidelines

Pain disorders related to psychological factors (TOC entry)

a. Pain disorders related to psychological factors ..................................................................... 43

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.5.a
Psychoactive substance use disorders (TOC entry)

b. Mental and behavioral disorders due to psychoactive substance use ................................... 43

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.5.b

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference F51.1 with the canonical source and edition:

F51.1 — Hypersomnia not due to a substance or known physiological condition. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/F51.1

Canonical URL: https://icd10codingpro.com/codes/F51.1

Related Codes

Parent Code

F51 Sleep disorders not due to a substance or known physiological condition

More Specific Codes

F51.11 Primary hypersomnia F51.12 Insufficient sleep syndrome F51.13 Hypersomnia due to other mental disorder F51.19 Other hypersomnia not due to a substance or known physiological condition

Related Codes in F51

F51 Sleep disorders not due to a substance or known physiological condition F51.0 Insomnia not due to a substance or known physiological condition F51.01 Primary insomnia F51.02 Adjustment insomnia F51.03 Paradoxical insomnia F51.04 Psychophysiologic insomnia F51.05 Insomnia due to other mental disorder F51.09 Other insomnia not due to a substance or known physiological condition F51.11 Primary hypersomnia F51.12 Insufficient sleep syndrome F51.13 Hypersomnia due to other mental disorder F51.19 Other hypersomnia not due to a substance or known physiological condition F51.3 Sleepwalking [somnambulism] F51.4 Sleep terrors [night terrors] F51.5 Nightmare disorder F51.8 Other sleep disorders not due to a substance or known physiological condition F51.9 Sleep disorder not due to a substance or known physiological condition, unspecified
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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