Chronic lower respiratory diseases
53 codes in this section
About Section J40-J4A
Section J40-J4A (J40-J4A) covers chronic lower respiratory diseases. It sits within the Diseases of the respiratory system chapter (J00-J99). This section contains 53 ICD-10-CM codes, 39 billable diagnoses you can submit on a claim, and 14 non-billable header codes used to organize the hierarchy.
Codes are organized below by 3-character root. Click the root to see all subcodes underneath it, or click any individual code for full coverage data, payer policies, and linked CPT procedures.
Codes in J40-J4A
Grouped by 3-character root code. Click any code for full detail.
| J41.0 | Simple chronic bronchitis | Billable |
| J41.1 | Mucopurulent chronic bronchitis | Billable |
| J41.8 | Mixed simple and mucopurulent chronic bronchitis | Billable |
| J43.0 | Unilateral pulmonary emphysema [MacLeod's syndrome] | Billable |
| J43.1 | Panlobular emphysema | Billable |
| J43.2 | Centrilobular emphysema | Billable |
| J43.8 | Other emphysema | Billable |
| J43.9 | Emphysema, unspecified | Billable |
| J44.0 | Chronic obstructive pulmonary disease with (acute) lower respiratory infection | Billable |
| J44.1 | Chronic obstructive pulmonary disease with (acute) exacerbation | Billable |
| J44.8 | Other specified chronic obstructive pulmonary disease | Header |
| J44.81 | Bronchiolitis obliterans and bronchiolitis obliterans syndrome | Billable |
| J44.89 | Other specified chronic obstructive pulmonary disease | Billable |
| J44.9 | Chronic obstructive pulmonary disease, unspecified | Billable |
| J45.2 | Mild intermittent asthma | Header |
| J45.20 | Mild intermittent asthma, uncomplicated | Billable |
| J45.21 | Mild intermittent asthma with (acute) exacerbation | Billable |
| J45.22 | Mild intermittent asthma with status asthmaticus | Billable |
| J45.3 | Mild persistent asthma | Header |
| J45.30 | Mild persistent asthma, uncomplicated | Billable |
| J45.31 | Mild persistent asthma with (acute) exacerbation | Billable |
| J45.32 | Mild persistent asthma with status asthmaticus | Billable |
| J45.4 | Moderate persistent asthma | Header |
| J45.40 | Moderate persistent asthma, uncomplicated | Billable |
| J45.41 | Moderate persistent asthma with (acute) exacerbation | Billable |
| J45.42 | Moderate persistent asthma with status asthmaticus | Billable |
| J45.5 | Severe persistent asthma | Header |
| J45.50 | Severe persistent asthma, uncomplicated | Billable |
| J45.51 | Severe persistent asthma with (acute) exacerbation | Billable |
| J45.52 | Severe persistent asthma with status asthmaticus | Billable |
| J45.9 | Other and unspecified asthma | Header |
| J45.90 | Unspecified asthma | Header |
| J45.901 | Unspecified asthma with (acute) exacerbation | Billable |
| J45.902 | Unspecified asthma with status asthmaticus | Billable |
| J45.909 | Unspecified asthma, uncomplicated | Billable |
| J45.99 | Other asthma | Header |
| J45.990 | Exercise induced bronchospasm | Billable |
| J45.991 | Cough variant asthma | Billable |
| J45.998 | Other asthma | Billable |
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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