F51.5 Nightmare disorder

Billable ICD-10-CM code, FY2026.

Applicable to

• Dream anxiety disorder

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

Excludes2 (not included here)

• organic sleep disorders (G47.-)

MS-DRG index

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

Approximate ICD-9-CM (GEMs)

• 307.47 Other dysfunctions of sleep stages or arousal from sleep (approximate)

Code annotations containing back-references to F51.5

Back-references to F51.5

• Type 2 Excludes: G47 Sleep disorders ("nightmares (F51.5)")

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 F51.5

• Disorder (of) › dream anxiety
• Disorder (of) › nightmare
• Disorder (of) › sleep › nightmares
• Nightmares (REM sleep type)

Nearby codes

• 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 (this code)
• 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