2025 ICD-10-CM Diagnosis Code L42

Pityriasis rosea

ICD-10-CM Code:
L42
ICD-10 Code for:
Pityriasis rosea
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Chronic
Code Navigator:

L42 is a billable diagnosis code used to specify a medical diagnosis of pityriasis rosea. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2024 through September 30, 2025.

Code Classification

  • Diseases of the skin and subcutaneous tissue
    L00–L99
    • Papulosquamous disorders
      L40-L45
      • Pityriasis rosea
        L42

Approximate Synonyms

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

  • Pityriasis rosea
  • Pityriasis rosea-like drug eruption

Clinical Classification

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

Other specified inflammatory condition of skin

CCSR Code: SKN002

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

Clinical Information

  • Pityriasis Rosea

    a mild exanthematous inflammation of unknown etiology. it is characterized by the presence of salmon-colored maculopapular lesions. the most striking feature is the arrangement of the lesions such that the long axis is parallel to the lines of cleavage. the eruptions are usually generalized, affecting chiefly the trunk, and the course is often self-limiting.
  • Pityriasis Rosea

    a mild, self-limited skin disorder that is most commonly seen in children and young adults. it is characterized by an initial large round spot on the chest, abdomen, or back, often referred to as a herald patch, that is usually followed within a week by a distinctive pattern of similar but smaller papules on the torso, arms, and legs. there may also be itching, especially when overheated.

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 L42 to ICD-9-CM

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

Pityriasis rosea

ICD-9-CM: 696.3

This is a direct match with no additional mapping qualifiers. The absence of a flag generally means the mapping is considered exact or precise. In other words, the ICD-10 code maps cleanly to the ICD-9 code without qualification, approximation, or needing multiple codes.

Patient Education


Skin Conditions

What does your skin do?

Your skin is your body's largest organ. It covers the entire outside of your body. There are many ways that your skin protects your body and helps keep you healthy. For example, it:

  • Holds body fluids in, which helps prevent you from getting dehydrated
  • Keeps out harmful germs, which helps prevent infections
  • Helps you feel things like heat, cold, and pain
  • Helps control your body temperature
  • Makes vitamin D when the sun shines on it
  • Shields your body against heat and light

What problems and conditions can affect your skin?

There are many different problems and conditions which can affect your skin. Some of them can cause uncomfortable symptoms, such as itching, burning, redness, and rashes. They might also affect your appearance. Some of the more common skin conditions include:

  • Acne, which causes pimples when hair follicles under your skin get clogged up
  • Burns
  • Cuts and scrapes
  • Dandruff, flaking of the skin on your scalp (the top of your head)
  • Eczema (atopic dermatitis), which causes inflammation, redness, and irritation of the skin
  • Hives, which are red and sometimes itchy bumps on your skin
  • Insect bites
  • Psoriasis, which causes itchy, scaly red patches
  • Skin cancer
  • Skin infections

How can I keep my skin healthy?

Since your skin protects your body in many ways, it's important to try to keep your skin healthy. For example, you can:

  • Wear the right protective equipment, like gloves, long sleeves, knee and elbow pads, or helmets to protect against cuts, bumps and scrapes.
  • If you do get a cut or scrape, clean it right away with soap and warm water. Put on a bandage to protect it while it heals.
  • When you are spending time outdoors, wear long sleeves and pants and use insect repellant to prevent insect bites.
  • Prevent sunburn by covering up and using sunscreen when outdoors.
  • Wash your hands often with soap and water.
  • When you take a shower or bath, use warm (not hot) water. Use mild cleansers and wash gently (don't scrub).
  • Use moisturizers, like lotions, creams, or ointments, to prevent dry skin.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


[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] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.