ICD-10-CM · Respiratory system
ICD-10-CM · Respiratory systemJ45.909: Unspecified asthma, uncomplicated
J45.909 is the ICD-10-CM code for Unspecified asthma, uncomplicated. Billable on U.S. claims with supporting documentation. Chapter: Respiratory system. Category: J45.
About this code
Unspecified asthma, uncomplicated.
J45.909 is an ICD-10-CM diagnosis code for unspecified asthma, uncomplicated. It sits in the 10. Respiratory system chapter of the U.S. clinical modification, under category J45.
This code is billable on U.S. healthcare claims when supported by appropriate clinical documentation. The patient chart must establish the diagnosis, capture any clinical detail encoded in the code (severity, laterality, encounter type, complications where applicable), and demonstrate medical necessity for the billed services.
Payer-specific coverage rules vary. Always cross-check against the current Local Coverage Determinations (LCDs) and National Coverage Determinations (NCDs) for the payer adjudicating the claim, plus any specialty-specific CMS Medicare Administrative Contractor guidance.
Billing context
What practitioners watch for on J45.909.
Code-specific billing guidance for J45.909, written from production billing experience.
Documentation
Unspecified asthma, uncomplicated. Document asthma severity (mild intermittent J45.20-22, mild persistent J45.30-32, moderate persistent J45.40-42, severe persistent J45.50-52) where assessed; use J45.909 only when severity is not characterized in the chart.
Common denial categories
- CO-16: Information missing or incorrect on the claim or in supporting documentation. Add documentation specificity that supports the coded detail; resubmit with corrected information.
- CO-50: Service not deemed medically necessary by the payer. Confirm the diagnosis-procedure relationship matches LCD/NCD coverage, attach clinical justification, appeal with documentation.
- CO-11: Diagnosis is inconsistent with the procedure performed. Verify the diagnosis-to-procedure pairing per payer policy; correct the linked diagnosis pointer or the procedure code.
Coverage signal
Asthma medication coverage typically requires step therapy or formulary tier matching for biologics. Pulmonary function testing is generally covered when documented exacerbation or new diagnosis.
Common specialties
Pulmonology · Family Medicine · Pediatrics · Urgent Care
Companion CPT codes
Procedures commonly billed alongside J45.909 based on Medonix client production data and CMS coding guidance.
- 94060Bronchodilator responsiveness, spirometry pre-post
- 94010Spirometry
- 99213Office visit, established
- 99214Office visit, established, moderate complexity
CPT is a registered trademark of the American Medical Association. Codes shown for educational reference only.
Related codes
Other codes in category J45.
- J45.20
Mild intermittent asthma, uncomplicated
Open - J45.21
Mild intermittent asthma with (acute) exacerbation
Open - J45.22
Mild intermittent asthma with status asthmaticus
Open - J45.30
Mild persistent asthma, uncomplicated
Open - J45.31
Mild persistent asthma with (acute) exacerbation
Open - J45.32
Mild persistent asthma with status asthmaticus
Open - J45.40
Moderate persistent asthma, uncomplicated
Open - J45.41
Moderate persistent asthma with (acute) exacerbation
Open
Sources
Where this entry comes from.
- NLM Clinical Tables Search Service: the official U.S. National Library of Medicine API for ICD-10-CM lookup.
- CDC National Center for Health Statistics: annual ICD-10-CM Tabular List release with effective date October 1.
- CMS Medicare Coverage Database: Local Coverage Determinations and National Coverage Determinations for payer-specific rules.
Frequently asked
About ICD-10 code J45.909.
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