Final answer:
Before administering Myochrysine to a client with rheumatoid arthritis, it is important for a nurse to check lab work to monitor the client's kidney function and blood counts for any potential medication toxicity.
Step-by-step explanation:
Before administering Myochrysine (gold sodium thiomalate) to a client with rheumatoid arthritis (RA), the nurse should check the lab work. This is important because gold preparations can lead to side effects including renal toxicity, and periodic lab work can help in monitoring the client's kidney function as well as blood counts to check for any toxicity arising from the medication. Unlike options such as administering an antiemetic, obtaining blood pressure, or administering a sedative, which may or may not be necessary based on the client's condition, checking lab work is a standard procedure before administering medications like Myochrysine that can have systemic effects.