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

Category / Non-billable header 17 subcodes

Block: Behavioral syndromes associated with physiological disturbances and physical factors (F50-F59)

Excludes 2 (not included here)

  • organic sleep disorders (G47.-)

Subcodes

Each subcode links to a detail page with full clinical annotations.

Code Description Billable
F51..0 Insomnia not due to a substance or known physiological condition No
F51..01 Primary insomnia Yes
F51..02 Adjustment insomnia Yes
F51..03 Paradoxical insomnia Yes
F51..04 Psychophysiologic insomnia Yes
F51..05 Insomnia due to other mental disorder Yes
F51..09 Other insomnia not due to a substance or known physiological condition Yes
F51..1 Hypersomnia not due to a substance or known physiological condition No
F51..11 Primary hypersomnia Yes
F51..12 Insufficient sleep syndrome Yes
F51..13 Hypersomnia due to other mental disorder Yes
F51..19 Other hypersomnia not due to a substance or known physiological condition Yes
F51..3 Sleepwalking [somnambulism] Yes
F51..4 Sleep terrors [night terrors] Yes
F51..5 Nightmare disorder Yes
F51..8 Other sleep disorders not due to a substance or known physiological condition Yes
F51..9 Sleep disorder not due to a substance or known physiological condition, unspecified Yes

Last reviewed: September 2026