F51.0Insomnia not due to a substance or known physiological condition

F51.0 is the ICD-10-CM diagnosis code for insomnia not due to a substance or known physiological condition. It belongs to category F51 (sleep disorders not due to a substance or known physiological condition), block F50-F59 (behavioral syndromes associated with physiological disturbances and physical factors) and chapter 5 (mental, Behavioral and Neurodevelopmental disorders). It is a header code, so it can't be reported by itself; one of its 6 subcodes must be used instead.

Within F51 (sleep disorders not due to a substance or known physiological condition), F51.0 is specifically for insomnia not due to a substance or known physiological condition. Related codes cover hypersomnia not due to a substance or known physiological condition (F51.1), Sleepwalking [somnambulism] (F51.3), sleep terrors [night terrors] (F51.4), Nightmare disorder (F51.5), other sleep disorders not due to a substance or known physiological condition (F51.8) and sleep disorder not due to a substance or known physiological condition, unspecified (F51.9).

To report this condition, pick the subcode that matches the documentation: F51.01 (insomnia), F51.02 (insomnia), F51.03 (insomnia), F51.04 (insomnia), F51.05 (disorder) and F51.09 (condition).

The conditions in its Excludes2 note aren't part of F51.0, but may be coded alongside it if the patient has both: alcohol related insomnia (F10.182, F10.282, F10.982), drug-related insomnia (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), insomnia NOS (G47.0-), insomnia due to known physiological condition (G47.0-) and 2 more.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.