The client is prescribed medications on hospital admission. Four days later the client's serum creatinine level, which was normal at admission, is now 3.7 mg/dL. The nurse should contact the HCP regarding a dosage change for which medication?

A: The nurse should contact the HCP regarding ceftriaxone (Rocephin). Ceftriaxone, a third-generation cephalosporin antibiotic, is 33% to 67% excreted in the urine unchanged. Dosage reduction or increased dosing interval is recommended in renal insufficiency because ceftriaxone is nephrotoxic and can further damage the kidneys. B: Insulin glargine (Lantus) is partially metabolized at the site of injection to active insulin metabolites and partially metabolized by the liver, the spleen, the kidney, and muscle tissue; no dose reduction is necessary unless serum glucose levels fluctuate. C: Diltiazem (Cardizem) is mostly metabolized by the liver; no dose reduction is necessary. D: Furosemide (Lasix) is 30% to 40% metabolized by the liver with some nonhepatic metabolism and renal excretion as unchanged medication; no dose reduction is necessary.