ICD-10 Code J45.40 – Moderate persistent asthma, uncomplicated (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J45.40 – Moderate persistent asthma, uncomplicated
What it is
J45.40 identifies moderate persistent asthma without documented complications. It is used for asthma that is ongoing and more than mild, but not described as severe or with an acute exacerbation.
Clinical signs
Clinical features vary; refer to documentation. Typical asthma findings include recurrent wheeze, cough, chest tightness, and shortness of breath, with symptoms that persist and affect normal activity.
When to use this code
Use J45.40 when the record clearly states moderate persistent asthma and does not mention an exacerbation, status asthmaticus, or another complication. It fits chronic asthma noted in outpatient, inpatient, or problem-list documentation. Check documentation if severity is unclear.
Do not use for
Do not use this code for mild, severe, or intermittent asthma, or when an acute exacerbation is documented. Also avoid it if the provider specifies a complication or a different asthma type.
Coding tip
Match the documented asthma severity exactly and confirm whether “uncomplicated” is supported by the note.