Rhabdomyolysis in a patient receiving ranolazine and simvastatin

Abstract

A case of rhabdomyolysis occurring shortly after the addition of ranolazine to a stable simvastatin regimen is reported. A 63-year-old Caucasian man with a history of hyperlipidemia and coronary artery disease arrived at an urgent care center with complaints of worsening bilateral lower-extremity weakness over three days. He was admitted to a hospital within 24 hours. His other underlying medical conditions included congestive heart failure, chronic kidney disease, degenerative joint disease, and a history of stroke. Oral medications at the time of admission included furosemide 40 mg daily, clopidogrel 75 mg daily, hydralazine 50 mg three times daily, metoprolol 50 mg twice daily, isosorbide mononitrate 120 mg daily, omeprazole 20 mg daily, nitroglycerin tablets as needed for chest pain, simvastatin 80 mg daily, and the recent addition of ranolazine 500 mg daily. Laboratory tests revealed that the patient's serum creatinine (SCr) concentration was 3.9 mg/dL and his creatine kinase (CK) concentration was 31,989 units/L. Ranolazine and simvastatin were discontinued, and metoprolol, hydralazine, isosorbide mono-nitrate, and furosemide were continued via nasogastric tube, along with amlodipine 10 mg daily and omeprazole 40 mg daily. The patient's serum CK concentration remained above 10,400 units/L for four days. By day 7 of hospitalization, the patient's serum CK concentration was 715 units/L, and it was almost undetectable by hospital day 18 (24 units/L). The patient's SCr concentration remained at his baseline value of 2.2 mg/dL. A 63-year-old man with a history of chronic renal impairment on a stable dosage of simvastatin developed rhabdomyolysis after the addition of ranolazine to his medication regimen.