F51.19 — Other hypersomnia not due to a substance or known physiological condition
F51.19 is a billable, specific ICD-10-CM code for other hypersomnia not due to a substance or known physiological condition. It is valid for submission on a claim.
Risk adjustment
F51.19 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
F51.19 is named in 11 Medicare coverage policies — 9 listing it as supporting medical necessity, and 2 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52434Health and Behavior Assessment/Intervention – Medical Policy Articlenot covered
- A56865Billing and Coding: Psychiatric Inpatient Hospitalizationnot covered
- A56612Billing and Coding: CT of the Head
- A56730Billing and Coding: Respiratory Therapy and Oximetry Services
How F51.19 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to F51.19.
- Hypersomnia›nonorganic origin›specified NEC
- Hypersomnia›not due to a substance or known physiological condition›specified NEC
Related codes at this level
Codes that share F51.1. If F51.19 is not quite right, the correct code is usually one of these.
Questions about F51.19
- Is F51.19 a billable ICD-10-CM code?
- Yes. F51.19 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does F51.19 sit in the tabular list?
- Mental, Behavioral and Neurodevelopmental disorders (F01-F99), in the block Behavioral syndromes associated with physiological disturbances and physical factors (F50-F59).