2021 ICD-10-CM Code F51.1

Hypersomnia not due to a substance or known physiological condition

Version 2021

Not Valid for Submission

F51.1 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of hypersomnia not due to a substance or known physiological condition. The code is not specific and is NOT valid for the year 2021 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

ICD-10:F51.1
Short Description:Hypersomnia not due to a substance or known physiol cond
Long Description:Hypersomnia not due to a substance or known physiological condition

Code Classification

Specific Coding for Hypersomnia not due to a substance or known physiol cond

Non-specific codes like F51.1 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for hypersomnia not due to a substance or known physiol cond:

  • BILLABLE CODE - Use F51.11 for Primary hypersomnia
  • BILLABLE CODE - Use F51.12 for Insufficient sleep syndrome
  • BILLABLE CODE - Use F51.13 for Hypersomnia due to other mental disorder
  • BILLABLE CODE - Use F51.19 for Other hypersomnia not due to a substance or known physiological condition

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code F51.1:


Type 2 Excludes

Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

Information for Patients


Sleep Disorders

What is sleep?

Sleep is a complex biological process. While you are sleeping, you are unconscious, but your brain and body functions are still active. They are doing a number of important jobs that help you stay healthy and function at your best. So when you don't get enough quality sleep, it does more than just make you feel tired. It can affect your physical and mental health, thinking, and daily functioning.

What are sleep disorders?

Sleep disorders are conditions that disturb your normal sleep patterns. There are more than 80 different sleep disorders. Some major types include

Some people who feel tired during the day have a true sleep disorder. But for others, the real problem is not allowing enough time for sleep. It's important to get enough sleep every night. The amount of sleep you need depends on several factors, including your age, lifestyle, health, and whether you have been getting enough sleep recently. Most adults need about 7-8 hours each night.

What causes sleep disorders?

There are different causes for different sleep disorders, including

Sometimes the cause is not known.

There are also some factors that can contribute to sleep problems, including

What are the symptoms of sleep disorders?

The symptoms of sleep disorders depend on the specific disorder. Some signs that you may have a sleep disorder include that

How are sleep disorders diagnosed?

To make a diagnosis, your health care provider will use your medical history, your sleep history, and a physical exam. You may also have a sleep study (polysomnogram). The most common types of sleep studies monitor and record data about your body during a full night of sleep. The data includes

Other types of sleep studies may check how quickly you fall asleep during daytime naps or whether you are able to stay awake and alert during the day.

What are the treatments for sleep disorders?

Treatments for sleep disorders depend on which disorder you have. They may include


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)