Question

After taking Simvastatin for 2 months, Mr. Booker reports weakness and myalgias in his legs. What would be the Nurse Practitioner's next steps and why ? Would you order any lab tests? The patient's LDL was 252 prior to starting the medication. Keep in mind that Mr. Booker suffered a myocardial infarction 5 years ago

Answer 1

• Simvastatin belongs to the statin group of drugs
• Statin is a lipid lowering agent.
• It inhibits hydroxy-3-methylglutaryl coenzyme A inhibitor.
• Common side effects of this group of drugs are
  • Myalgia, myopathy, rhabdomyolysis
  • Hypersensitivity
  • Deranged liver enzyme
  • Increase blood sugar level
  • Increase in creatinine phosphokinase levels.
• Mr Booker is having myalgia. This is a side effect of simvastatin.
• The nurse should first counsell the patient about the side effect a d re-assure the patient.
• The nurse should send blood creatinine kinase level.
• If the levels of CK is > 5 times the upper limit of normal or if the symptoms of myalgia is severe then discontinue the drug.
• The patients renal function (serum creatinine and blood urea nitrogen) and serum electrolytes ( potassium) should monitored. This is because simvastatin increases the risk of myopathy and rhabdomyolysis. The release of myoglobin of muscle into the blood and then enter the kidney.
• This can damage the kidney.
• Simivastatin can re- introduced after CK levels come back to normal at a lower dose.

Risk of myopathy with simvastatin increases with

1. Dose of 80mg /day
2. Coadministration with Niacin
3. Drugs like amlodepine, verampamil, diltrazem
4. Concomitant hypothyroidism and renal failure
5. Chinese decent.