In rare cases, Zocor can cause a condition that results in the breakdown of skeletal muscle tissue, potentially leading to kidney failure. Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.
Never take Zocor in larger amounts, or for longer than recommended by your doctor. Follow your doctor's dosing instructions very carefully. Taking too much of this medication may cause serious or life-threatening side effects.
Before taking Zocor, tell your doctor if you have ever had liver or kidney disease, diabetes, or a thyroid disorder, if you are of Chinese descent, or if you drink more than 2 alcoholic beverages daily.
Zocor can harm an unborn baby or cause birth defects. Do not use if you are pregnant or planning to become pregnant.
Grapefruit and grapefruit juice may interact with simvastatin and lead to potentially dangerous effects. Do not consume grapefruit products while taking this medication.
Some medicines can cause unwanted or dangerous effects when used with Zocor. Your doctor may need to change your treatment plan if you use certain antibiotics or antifungal medicines, hepatitis C medication, heart medication, or medicines to treat HIV/AIDS.
Stop taking this medication and tell your doctor right away if you become pregnant.
Before taking this medicine
You should not take Zocor if you are allergic to simvastatin, if you are pregnant or breast-feeding, or if you have active liver disease.
The following drugs can increase your risk of serious muscle problems if you take them together with Zocor. These drugs should not be used while you are taking Zocor:
cyclosporine;
danazol;
gemfibrozil;
nefazodone;
an antibiotic - clarithromycin, erythromycin, telithromycin;
antifungal medication - itraconazole, ketoconazole, posaconazole, voriconazole;
hepatitis C medications - boceprevir, telaprevir; or
HIV/AIDS medication - atazanavir, cobicistat (Stribild, Tybost), darunavir, fosamprenavir, indinavir, nelfinavir, ritonavir, saquinavir, tipranavir.
Before you start taking Zocor, tell your doctor if you are already using any of these other medicines:
lomitapide; or
heart medication - amiodarone, amlodipine, diltiazem, dronedarone, ranolazine, verapamil.
To make sure Zocor is safe for you, tell your doctor if you have:
history of liver disease;
history of kidney disease;
diabetes;
a thyroid disorder; or
if you drink more than 2 alcoholic beverages daily.
Zocor can cause a condition that results in the breakdown of skeletal muscle tissue, potentially leading to kidney failure. This condition may be more likely to occur in older adults and in people who have kidney disease or poorly controlled hypothyroidism (underactive thyroid).
FDA pregnancy category X. This medicine can harm an unborn baby or cause birth defects. Do not take Zocor if you are pregnant. Stop taking this medication and tell your doctor right away if you become pregnant. Use effective birth control to avoid pregnancy while you are taking this medicine.
Simvastatin may pass into breast milk and could harm a nursing baby. Do not breast-feed while you are taking Zocor.
 Zocor pregnancy and breastfeeding warnings (more detail)
