A nurse is caring for a client who has a new prescription for metformin. Which of the following laboratory results should the nurse evaluate prior to administering the first dose?

Before administering the first dose of metformin, the nurse should evaluate the client's creatinine level. Metformin is primarily excreted by the kidneys, and its clearance from the body depends on the renal function. If the client has impaired kidney function, metformin can accumulate in the body and lead to potential adverse effects, particularly lactic acidosis.

Monitoring the creatinine level helps assess the client's kidney function and determines whether it is safe to administer metformin. If the creatinine level is elevated, indicating reduced kidney function, the nurse should consult with the healthcare provider to determine the appropriate dose adjustment or consider an alternative treatment option.

Let's go through the other options and explain why they are not the priority laboratory results to evaluate before administering metformin:

A. Potassium level: While monitoring potassium levels is important in some situations, it is not a primary concern before administering metformin. Metformin does not have a significant effect on potassium levels, and it is not a medication known for causing hypokalemia (low potassium levels).

C. Platelet count: Metformin does not have a direct impact on platelet count, and evaluating platelet count is not typically required before starting metformin therapy. Platelet count monitoring may be relevant for certain other medications or medical conditions, but it is not specific to metformin administration.

D. Liver enzymes: While it is essential to monitor liver function in clients on long-term metformin therapy, evaluating liver enzymes before the first dose of metformin is not the priority. Metformin is primarily cleared by the kidneys, and liver enzymes are not directly affected by its initial administration. However, ongoing monitoring of liver function may be necessary during long-term