ICD-10 Code for asthma

The ICD-10-CM code for asthma is J45.909 when documented without further specification. Asthma coding is severity-first: the J45 4th character encodes mild-intermittent through severe-persistent, and the 6th character encodes uncomplicated vs exacerbation vs status asthmaticus.

Which Code Should You Use?

J45.909 — Unspecified asthma, uncomplicated

Unspecified asthma, uncomplicated - severity not documented.

J45.901 — Unspecified asthma with (acute) exacerbation

Unspecified asthma WITH acute exacerbation.

J45.902 — Unspecified asthma with status asthmaticus

Unspecified asthma with status asthmaticus.

J45.40 — Moderate persistent asthma, uncomplicated

Moderate persistent asthma, uncomplicated.

J44.9 — Chronic obstructive pulmonary disease, unspecified

COPD documented (with or without asthma overlap, see J44 notes).

What to Document

  • Severity classification (intermittent / mild / moderate / severe persistent).
  • Exacerbation or status asthmaticus at the encounter.
  • Tobacco use/exposure (use additional code Z72.0, F17.-, Z77.22).

Coding Notes

Severity documentation upgrades the page-one J45.90- codes to the severity-specific families (J45.2x/3x/4x/5x). Cough-variant asthma is J45.991.

References

Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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