Patients who take 80-mg Zocor, the highest dose, have an increased risk of myopathy and rhabdomyolysis, which can lead to deadly kidney failure. The FDA has restricted the highest dose of Zocor to 40-mg per day. They have also warned about the risk of combining Zocor with amiodarone, a popular anti-arrhythmic medication.
UPDATE: Study Links Lipitor to 9-27% Increased Risk of Cataracts
September 23, 2013 — Study links Lipitor and other statins to a 9-27% increased risk of cataracts. Longer use of the drugs is associated with a higher risk of cataracts. Click here to read more.
Zocor: An Overview
FDA approved in December 1991, Zocor (simvastatin) is used together with diet and exercise to reduce the amount of “bad cholesterol” (known as low-density lipoprotein or LDL) in the blood. High levels of LDL have been linked to higher risks of heart attack, stroke and cardiovascular death.
In 2010, about 2.1 million people in the United States were prescribed a product containing simvastatin 80 mg, according to the FDA.
Zocor is manufactured by Merck & Co., Inc. and belongs to a group of drugs known as statins. Simvastatin is sold as a single-ingredient product (Zocor), or it is sold in combination with ezetimibe as Vytorin and in combination with niacin as Simcor.
In June 2011, the FDA recommended limiting use of the highest approved dose of the cholesterol-lowering medication because of increased risk of muscle damage, or myopathy. Patients taking the 80 mg dose of Zocor have an increased risk of myopathy compared to patients taking lower doses of the same drug or other drugs in the same class. The risk is especially high during the first year of treatment. Zocor-induced myopathy may be the result of interactions with other medicines and may be associated with a genetic predisposition.
The most serious form of myopathy is known as rhabdomyolysis, which is a rare condition requiring hospitalization in 4.9 people in 100,000 patients who used simvastatin for one full year.
As a result of the risk of muscle injury, the FDA has updated the labels for Zocor, Vytorin, and Simcor to include new dosing restrictions for the 80-mg dose. It is also being updated with new recommendations in pairing certain medications with simvastatin, as they they may increase levels of simvastatin in the body, leading to higher risks of myopathy.
Due to the risk of muscle injury associated with Zocor, you or someone you know may want to contact a Zocor lawyer or attorney with The Clark Firm to discuss the potential for a Zocor lawsuit.
Symptoms of Myopathy and Rhabdomyolysis
Signs and symptoms of Zocor-induced myopathy or rhabdomyolysis include:
- Muscle pain
- Muscle stiffness
- Muscle tenderness
- Muscle weakness
- Dark or red colored urine
- Unexplained tiredness
- Elevation of muscle enzyme in the blood
FDA Zocor Studies
In June 2011, the FDA reviewed a seven-year clinical trail that compared the efficacy and safety of simvastatin 80 mg to simvastatin 20 mg. The study was known as the Study of the Effectiveness of Additional Reductions in Cholesterol and Homocysteine (SEARCH).
At the end of SEARCH, 52 patients in the 80-mg group developed myopathy, compared to just one patient in the 20-mg group. Twenty-two patients in the 80-mg group developed rhabdomyolysis, compared to zero patients in the 20-mg group.
The risks of myopathy, including rhabdomyolysis, with 80-mg Zocor were highest in the first 12 months of treatment. Additionally, older populations and women had an increased risk of myopathy.
The findings of SEARCH also reflected the results of other studies. The FDA received a higher number of fatal rhabdomyolysis Adverse Events Reports with 80 mg users, compared to lower doses of simvastatin or lower doses of other statins. Furthermore, other clinical data show higher overall rates of myopathy and rhabdomyolysis in patients with simvastatin 80 mg.
On June 8, 2011 the FDA released a set of new recommendations for Zocor users. Based upon the elevated risk of muscle injury or myopathy, especially during the first 12 months of use, the agency is making the following recommendations:
- Simvastatin 80 mg should only be used in patients who have been taking it for longer than 12 months or more and have not experienced any muscle toxicity.
- Simvastatin 80 mg should not be prescribed to new patients.
- Patients who are unable to adequately lower their level of LDL on simvastatin 40 mg should not be given the higher 80 mg dose of simvastatin; instead, they should be placed on an alternative LDL-lowering treatment.
Simvastatin Dose Limitations
Because using simvastatin simultaneously with other certain medicines may increase the chance of myopathy or muscle injury, the FDA is adding information about simvastatin pairings with other medications to the drug label. Patients taking any form of simvastatin should not take any of the following medications at doses above what is recommended by the FDA. These recommendations include:
Do not use simvastatin with:
- HIV protease inhibitors
Do not exceed 10 mg simvastatin daily with:
Do not exceed 20 mg simvastatin daily with:
Rhabdomyolysis is the rapid breakdown of skeletal muscles in the body, which causes myoglobin (a muscle protein) to leak into the blood. When this occurs, myoglobin is filtered out of the body through the kidneys, sometimes causing a dark or red discoloration of the urine. Myoglobin can also be harmful to the kidneys. Severe cases of rhabdomyolysis are associated with kidney damage and kidney failure. It can even lead to hospitalization, dialysis and death in rare cases.