ICD-10 Code J99 – Respiratory disorders in diseases classified elsewhere (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J99 – Respiratory disorders in diseases classified elsewhere
What it is
J99 identifies respiratory disorders that are caused by another underlying disease. Use it when the pulmonary problem is documented as secondary to a different condition, not as a primary lung diagnosis.
Clinical signs
Clinical features vary; refer to documentation. Findings may include cough, dyspnea, wheezing, or other respiratory impairment linked to the underlying disease.
When to use this code
Use J99 when the provider states the respiratory disorder is due to another classified condition and does not assign a more specific code. It is appropriate for secondary respiratory involvement where the cause is documented elsewhere in the record. Code the underlying disease first when instructed by the classification.
Do not use for
Do not use J99 for primary respiratory diseases with their own specific ICD-10-CM code. Do not use it if the documentation does not clearly link the respiratory disorder to another condition; check documentation.
Coding tip
Always capture the underlying disease and any specific respiratory manifestation before assigning J99.