When coding for an adverse effect, what should be coded first?

When coding for an adverse effect, the nature of the adverse effect should be coded first. This approach aligns with coding guidelines that emphasize accurately describing the medical condition or event before detailing any contributing factors, such as medications or specific patient circumstances. By coding the nature of the adverse effect first, you ensure that the primary issue—the specific adverse event—is clearly documented.

This foundational step helps to establish the context for the coding of any additional related information, which may include the medication involved or other relevant factors. Thus, focusing on the nature of the adverse effect allows for a more precise and comprehensive capturing of the patient's medical history and the incident being reported. This main code generally reflects the condition that required medical attention, which is crucial for proper treatment and billing practices.