J45.4 is a "category code," which means it's non-billable. Billable codes require more specificity. Use the list below to navigate to codes that are more specific:
10
J45.40
Moderate persistent asthma, uncomplicated
Billable
10
J45.41
Moderate persistent asthma with (acute) exacerbation
Billable
10
J45.42
Moderate persistent asthma with status asthmaticus
Billable