The nurse is caring for a client who is taking atorvastatin to assist in lowering his LDL cholesterol. Which lab value must be routinely done with this medication to prevent complications?

A) Platelet counts: Monitoring platelet counts is not necessary with atorvastatin therapy. While certain medications may affect platelet levels, atorvastatin primarily targets lipid levels and does not have a significant impact on platelet function. B) Lung function test: Lung function tests are not relevant for atorvastatin use. These tests are typically utilized for assessing respiratory conditions and are not part of the routine monitoring for cholesterol-lowering medications. C) Liver function test: Atorvastatin can affect liver function, so it is essential to monitor liver enzymes (such as AST and ALT) regularly. Routine liver function tests help identify any potential hepatotoxicity early, allowing for timely intervention if liver function declines. D) Bun and creatinine levels: While monitoring renal function can be important in some contexts, it is not a routine requirement specifically for atorvastatin. However, it may be necessary in certain patient populations or if there are concerns about kidney function, but liver function tests are the primary focus with this medication.