Hypersomnia, unspecified

This code signifies a primary sleep disorder characterized by excessive daytime sleepiness or prolonged nighttime sleep, not attributable to insufficient sleep, another medical condition, medication, or substance use. Patients experience recurrent episodes of irresistible need to sleep, lapsing into sleep, or prolonged sleep episodes.

Utilize this code when documentation clearly indicates a diagnosis of hypersomnia without further specification of its type (e.g., idiopathic, recurrent, due to a medical condition). This is appropriate when the underlying cause of the hypersomnia has not been determined or is not documented.

• Avoid using this code if the type of hypersomnia is known; instead, use a more specific code from the G47.1 subcategory.
• Ensure documentation explicitly states "hypersomnia, unspecified" or similar language indicating the lack of further diagnostic clarity.
• Do not confuse with narcolepsy (G47.4-) or other sleep disorders where excessive sleepiness is a symptom but not the primary diagnosis.