2024 ICD-10-CM Diagnosis Code L21.9

Seborrheic dermatitis, unspecified

ICD-10-CM Code:
L21.9
ICD-10 Code for:
Seborrheic dermatitis, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

Code Classification

  • Diseases of the skin and subcutaneous tissue
    (L00–L99)
    • Dermatitis and eczema
      (L20-L30)
      • Seborrheic dermatitis
        (L21)

L21.9 is a billable diagnosis code used to specify a medical diagnosis of seborrheic dermatitis, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

Unspecified diagnosis codes like L21.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acute seborrheic dermatitis
  • Chronic seborrheic dermatitis
  • Disorder of skin due to human immunodeficiency virus infection
  • Generalized seborrheic dermatitis
  • Genitocrural seborrheic dermatitis
  • Perianal dermatitis
  • Perianal seborrheic dermatitis
  • Seborrhea faciei
  • Seborrheic blepharitis
  • Seborrheic dermatitis
  • Seborrheic dermatitis due to human immunodeficiency virus infection
  • Seborrheic eczema-like eruption
  • Truncal seborrheic dermatitis
  • Truncal seborrheic dermatitis
  • Truncal seborrheic dermatitis

Clinical Classification

Tabular List of Diseases and Injuries

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


Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
  • Seborrhea NOS

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Convert L21.9 to ICD-9-CM

  • ICD-9-CM Code: 690.10 - Sebrrheic dermatitis NOS
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
  • ICD-9-CM Code: 706.3 - Seborrhea
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education


Dandruff, Cradle Cap, and Other Scalp Conditions

Your scalp is the skin on the top of your head. Unless you have hair loss, hair grows on your scalp. Different skin problems can affect your scalp.

Dandruff is a flaking of the skin. The flakes are yellow or white. Dandruff may make your scalp feel itchy. It usually starts after puberty, and is more common in men. Dandruff is usually a symptom of seborrheic dermatitis, or seborrhea. It is a skin condition that can also cause redness and irritation of the skin.

Most of the time, using a dandruff shampoo can help control your dandruff. If that does not work, contact your health care provider.

There is a type of seborrheic dermatitis that babies can get. It is called cradle cap. It usually lasts a few months, and then goes away on its own. Besides the scalp, it can sometimes affect other parts of the body, such as the eyelids, armpits, groin, and ears. Normally, washing your baby's hair every day with a mild shampoo and gently rubbing their scalp with your fingers or a soft brush can help. For severe cases, your health care provider may give you a prescription shampoo or cream to use.

Other problems that can affect the scalp include:

  • Scalp ringworm, a fungal infection that causes itchy, red patches on your head. It can also leave bald spots. It usually affects children.
  • Scalp psoriasis, which causes itchy or sore patches of thick, red skin with silvery scales. About half of the people with psoriasis have it on their scalp.

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • 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. This was the first year ICD-10-CM was implemented into the HIPAA code set.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.