Healthcare Insights
Top ICD-10 codes for asthma
Asthma is a chronic condition that causes inflammation, swelling and narrowing of the airways in the lungs. This can lead to persistent bouts of coughing, difficulties breathing, chest pain and other symptoms that can majorly interfere with a person’s daily life. According to the CDC, asthma is one of the most common non-communicable diseases affecting both children and adults globally. The latest CDC data shows that nearly 25 million people have asthma.
Below, we’ve listed the 10 most common asthma diagnoses, and the ICD-10 codes physicians and medical coders use to classify them.
| Rank | ICD-10 code | ICD-10 description | % total patients | % total charges | Explore dataset |
|---|---|---|---|---|---|
| 1 | J45909 | Unspecified asthma, uncomplicated | 36.41% | 29.25% | Explore |
| 2 | J4520 | Mild intermittent asthma, uncomplicated | 19.36% | 0.89% | Explore |
| 3 | J4540 | Moderate persistent asthma, uncomplicated | 8.97% | 0.94% | Explore |
| 4 | J45901 | Unspecified asthma with (acute) exacerbation | 7.69% | 1.24% | Explore |
| 5 | J4530 | Mild persistent asthma, uncomplicated | 7.46% | 0.65% | Explore |
| 6 | J4521 | Mild intermittent asthma with (acute) exacerbation | 4.68% | 1.07% | Explore |
| 7 | J45998 | Other asthma | 3.69% | 1.01% | Explore |
| 8 | J4541 | Moderate persistent asthma with (acute) exacerbation | 2.87% | 1.48% | Explore |
| 9 | J4550 | Severe persistent asthma, uncomplicated | 2.26% | 25.38% | Explore |
| 10 | J45990 | Exercise induced bronchospasm | 2.09% | 22.64% | Explore |
Fig. 1 Data from the Atlas All-Payor Claims dataset. Claims data is sourced from multiple medical claims clearinghouses in the United States and updated monthly. Data accessed September 2025.
What are the ICD-10 codes for asthma?
Unspecified asthma, uncomplicated, ranks at the top of our list, representing 41.6% of total asthma diagnoses made by healthcare professionals in 2023. The ICD-10 code for asthma, unspecified is J45909.
This chronic condition has a considerable lead in both diagnoses and charges compared to all other ICD-10 codes. While many factors could contribute to why J45909 ranks number one, a likely cause could be problems with documentation. Many of the other codes on this list detail asthma of various degrees of chronicity and severity. A lack of proper documentation, however, could cause medical coders to resort to classifying the diagnosis as unspecified asthma, uncomplicated.
An asthma attack, also called “asthma, exacerbation,” is another common diagnosis with a few top positions on our list. The ICD-10 codes for these diagnoses are J45901, J4521, J4541, and J4531.
It’s also important to note that some physicians may regard asthma classifications as fluid. While this condition can’t be cured, a patient’s lifestyle can make the symptoms of asthma easier or harder to manage. Eliminating smoking habits and exercising regularly, alongside medical treatment, can potentially improve a patient’s condition. As a result, the classification of asthma a patient is diagnosed with can change over years and decades.
What are ICD-10 codes?
ICD-10 codes, or International Classification of Diseases, 10th Revision, are standardized alphanumeric codes used by healthcare providers, insurance companies, and public health agencies worldwide. These codes classify and code all diagnoses, symptoms, and procedures recorded with hospital care.
They are used primarily for billing, reporting diseases and health conditions, and ensuring consistency in health records globally. They also help in tracking disease trends and healthcare outcomes.
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