Pulmonology Coding Alert

Question: A pulmonologist in our practice prescribed formoterol to a patient with chronic obstructive pulmonary disease (COPD). Two days later, the patient called our practice saying they were experiencing nausea, vomiting, diarrhea, an increased heart rate, and a severe headache. The pulmonologist asked the patient to return to the office, where they performed an exam, drew blood, and determined the patient’s symptoms were side effects caused by the medication.

Should I report the diagnosis code for side effects or the COPD?

Texas Subscriber

Answer: You may need to code both the patient’s COPD and any side effects the patient is presenting. However, make sure to check the physician’s notes to determine if the patient took the medication correctly. If the patient did not take the prescribed medication as directed, then you would assign a poisoning code. Assuming the patient simply experienced adverse reactions to the medicine, you’ll first code the symptoms.

You’ll assign combination code R11.2 (Nausea with vomiting, unspecified) to report nausea and vomiting. For the patient’s diarrhea and severe headache, you’ll assign codes R19.7 (Diarrhea, unspecified) and R51.9 (Headache, unspecified), respectively. For the increased heart rate, look up Heart beat > rapid in the ICD-10-CM code set Alphabetic Index, where you’ll find R00.0 (Tachycardia, unspecified). When you verify the code in the Tabular List, you’ll see the additional synonym “Rapid heart beat.”

Additionally, you’ll need to report the medication that’s causing the adverse effects. Locating the adverse effect code is like locating a diagnosis code. However, instead of using the Alphabetic Index, you’ll open the Table of Drugs and Chemicals in your ICD-10-CM code set. In the Table of Drugs and Chemicals, you won’t find formoterol. The medication is a long-acting bronchodilator, so if you search for Bronchodilator NEC in the table, you’ll find T48.6X5- (Adverse effect of antiasthmatics) under the Adverse effect column. When you verify T48.6X5- in the Tabular list, you’ll find the code with a 7th character required icon, so you’ll add “A” to the end of the code to signify the visit as an initial encounter. In summation, you’ll assign T48.6X5A to report the adverse effect of the formoterol.

Remember: ICD-10-CM guideline I.C.19.e.1 instructs you to not code directly from the Table of Drugs and Chemicals. You must always verify the code in the Tabular List, as additional characters or codes may be required for correct reporting.