The nurse is caring for an older adult patient who is receiving multiple medications. When monitoring this patient for potential drug toxicity, the nurse should review which lab values closely?

A. Complete blood count (CBC) and serum glucose levels are important for overall health monitoring but do not specifically assess drug metabolism or excretion, which are key factors in drug toxicity. B. Pancreatic enzymes and urinalysis are useful for detecting pancreatic disorders and infections but are not primary indicators of drug toxicity. C. Serum creatinine and liver function tests (LFTs) are critical for monitoring drug toxicity, especially in older adults. The kidneys and liver are responsible for drug metabolism and excretion. Impaired kidney function, indicated by elevated serum creatinine, can lead to drug accumulation and toxicity. Abnormal LFTs suggest liver dysfunction, which can affect drug metabolism and increase toxicity risk. D. Serum lipids and electrolytes are important for cardiovascular and metabolic health but do not directly assess drug metabolism or toxicity risk.