Question: A patient with a history of asthma (controlled by medication) came in complaining of congestion, a bad cough, and difficulty breathing. The provider diagnosed a common cold and prescribed temporary use of a steroid inhaler to address the asthmatic cough exacerbated by the cold. Do I code the asthma first or the cold? Oregon Subscriber Answer: You’ll code the cold first, then the asthma —but not for the reason you might think. Let’s take a closer look. As you are probably aware, ICD-10-CM Official Guidelines, Section I.B.8 says, “If the same condition is described as both acute (subacute) and chronic, and separate subentries exist in the Alphabetic Index at the same indentation level,” sequence the acute code first and the chronic code second. However, this rule doesn’t apply in your case. Notice that when you look up “Asthma” in the alphabetic index, it lists neither “acute” nor “subacute” as a subentry at the same indentation level as “chronic obstructive.” In the scenario you describe, the cold is the primary reason for the encounter. The patient is presenting with cold symptoms and seeking treatment related to those symptoms. The chronic asthma impacts treatment like any comorbid condition, as evidenced by the prescription of the inhaler, which would not be typical for someone with a cold. Therefore, you’ll report J00 (Acute nasopharyngitis [common cold]), then list J45.901(Unspecified asthma with (acute) exacerbation) as the second code.