F51.11 Primary hypersomnia

Billable ICD-10-CM code, FY2026.

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

Excludes2 (not included here)

• organic sleep disorders (G47.-)

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

Excludes2 (not included here)

• 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-)

MS-DRG index

Defines the logic of DRG(s) 887 in MDC 19.

Approximate ICD-9-CM (GEMs)

• 307.44 Persistent disorder of initiating or maintaining wakefulness (approximate)

Code annotations containing back-references to F51.11

Back-references to F51.11

• Type 2 Excludes: G47.1 Hypersomnia ("primary hypersomnia (F51.11)")

Back-references to F51.1

• Type 2 Excludes: G47.1 Hypersomnia ("hypersomnia not due to a substance or known physiological condition (F51.1-)")

Back-references to F51

• Type 2 Excludes: F98 Other behavioral and emotional disorders with onset usually occurring in childhood and adolescence ("sleep disorders not due to a substance or known physiological condition (F51.-)")
• Type 2 Excludes: G47 Sleep disorders ("nonorganic sleep disorders (F51.-)")

Diagnosis Index entries for F51.11

• Hypersomnia (organic) › nonorganic origin
• Hypersomnia (organic) › not due to a substance or known physiological condition
• Hypersomnia (organic) › primary
• Somnolence › nonorganic origin

Nearby codes

• 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
• F51.1 Hypersomnia not due to a substance or known physiological condition
• F51.11 Primary hypersomnia (this code)
• 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]