The nurse is assessing a client who was recently diagnosed with Parkinson's disease and is taking carbidopa-levodopa. The client is concerned that the medication is not working. Which intervention should the nurse implement first?

A) Ask if the client's morning voids are dark colored: While this question may provide some information about hydration or possible side effects, it does not directly address the client's primary concern regarding the effectiveness of the medication. B) Explore what the client means by the drug "is not working": This is the most appropriate first intervention. Understanding the client's specific concerns, symptoms, or changes in their condition will help clarify the situation and guide further assessment or education. The client may have misconceptions about the medication's effects or may be experiencing variations in symptom control. C) Evaluate the client for signs of dyskinesia: Assessing for dyskinesia is important, especially in clients on long-term levodopa therapy. However, it is not the immediate step in addressing the client's concern about the medication's effectiveness. D) Determine if the client is taking the medication before meals: This is also relevant because the timing of medication can affect its absorption and efficacy. However, this intervention should follow understanding the client’s concerns first to provide a more comprehensive response.