Zocor (Simvastatin) - Oral

What Is Zocor?

Zocor (simvastatin) is a prescription drug used with diet and exercise to lower cholesterol. Zocor contains the active ingredient simvastatin. This medication is in a drug class called HMG CoA reductase inhibitors. This class is also known as statins.

Zocor is available as an oral tablet in both name-brand and generic forms. Simvastatin also comes in an oral suspension under the brand name FloLipid. Patients who cannot swallow pills can use FloLipid.

Zocor works by blocking an enzyme and slowing down cholesterol production in the body. By doing so, Zocor lowers the amount of cholesterol that can build up in the arteries and block blood flow to the heart, brain, and other areas of the body to help prevent problems like heart attacks and strokes.

Drug Facts

Generic Name: Simvastatin

Brand Name(s): Zocor

Administration Route(s): Oral

Drug Availability: Prescription

Therapeutic Classification: Antihyperlipidemic

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Simvastatin

Dosage Form(s): Tablet

What Is Zocor Used For?

The Food and Drug Administration (FDA) approved Zocor, along with diet and exercise, to lower cholesterol and triglycerides in adults 18 years and older.

Zocor lowers the risk of dying from heart attacks, strokes, and other heart complications in people with diabetes, coronary heart disease, or other risk factors. It also reduces the need for surgery in people at high risk for heart attacks. In some cases, adolescents who have started their menstrual period, or those aged 10–17 years who have high cholesterol and have not benefited from diet changes, may also use Zocor.

Zocor (Simvastatinl) Drug Information

Verywell / Zoe Hansen

How to Take Zocor

Take Zocor as instructed by your healthcare provider, usually once daily in the evening. You can take the Zocor tablet with or without food.

FloLipid suspension is generally taken every evening on an empty stomach. Take it one hour before or two hours after eating. Shake the suspension well for at least 20 seconds before using it. Measure the suspension with a proper measuring device. Your pharmacist can provide you with an oral syringe or measuring spoon. Do not use kitchen measuring tools because they are not as accurate. Use FloLipid within 30 days of opening the bottle.

It is best to take simvastatin at the same time every day. Do not take more simvastatin or less simvastatin than prescribed to you.

Keep taking your simvastatin unless your provider tells you to stop. Avoid grapefruit and grapefruit juice while on this medication. Grapefruit can increase the amount of medication in your bloodstream.


Store simvastatin tablets at room temperature (68–77 degrees Fahrenheit) and away from heat, direct light, and moisture. Simvastatin suspension (FloLipid) should also be stored at room temperature. Do not place it in the refrigerator or freezer. Use FloLipid within 30 days of opening the bottle. Keep simvastatin out of the reach of children and pets.

Off-Label Uses

Sometimes, healthcare providers prescribe a drug off-label for medical conditions that the FDA has not approved. The provider has deemed the treatment clinically appropriate for these uses in these cases.

Zocor’s off-label uses include to:

  • Slow the progression of a buildup of plaque (fatty deposits on the walls of arteries) in adults
  • Prevent narrowing of blood vessels in the brain after aneurysmal subarachnoid hemorrhage, a bulging blood vessel that bursts in the brain, which is a medical emergency
  • Treat cholesterol levels in children under 10 years old with severely high cholesterol or certain risk factors

How Long Does Zocor Take to Work?

A single dose of Zocor reaches its maximum effect by 2.4 hours. Your cholesterol levels should start lowering within several weeks of starting the medication. Your healthcare provider will check cholesterol levels in about four weeks and every few months after that.

What Are the Side Effects of Zocor?

This is not a complete list of side effects, and others may occur. A medical professional can advise you on side effects. If you experience other effects, contact your pharmacist or a medical professional. You may report side effects to the FDA at www.fda.gov/medwatch or 800-FDA-1088.

Like other medications, Zocor may cause side effects. Tell your healthcare provider about any side effects you experience while taking this medication.

Common Side Effects

The most common side effects of Zocor are:

  • Headache 
  • Upper respiratory infection/cold symptoms
  • Stomach problems (pain, constipation, nausea, and inflammation)
  • Dizziness 
  • Eczema (itchy skin and inflammation)
  • Diabetes (condition that affects the way the body uses blood sugar)
  • Trouble sleeping
  • Muscle pain
  • Abnormal liver function tests 
  • Urinary tract infection
  • Swelling of the hands, arms, legs, and feet
  • Problems with thinking and memory

Severe Side Effects

Call your healthcare provider right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Serious side effects and their symptoms can include the following:

  • Myopathy (muscle disease), including an increased risk with the 80 milligram (mg) dose of Zocor
  • Rhabdomyolysis (a life-threatening condition caused by muscle breakdown), including an increased risk with the 80 mg dose of Zocor
  • Immune-mediated necrotizing myopathy (muscle disease and weakness caused by an autoimmune response)
  • Tendon rupture (tendons connect muscles to bones)
  • Kidney failure
  • Liver problems
  • Inflamed pancreas (gland that aids digestion and regulates blood sugar)
  • Diabetes 
  • Lung tissue scarring
  • Severe allergic reactions (including hives, difficulty breathing, and swelling around the face, lips, tongue, or throat)
  • Sensitivity to light
  • Erythema multiforme (a skin disorder with bullseye-shaped lesions)
  • Stevens-Johnson syndrome (a serious reaction, with symptoms of fever and painful, blistering rashes)
  • Toxic epidermal necrolysis (a life-threatening skin disorder with peeling and blistering skin)
  • Low platelet levels
  • Low white blood cells
  • Destruction of red blood cells

Long-Term Side Effects

Mild long-term effects of Zocor can include:

  • Infection
  • Muscle cramps
  • Sensitivity to light
  • Rash
  • Hair loss
  • Joint pain and stiffness
  • Numbness and tingling
  • Weakness
  • Deficiency in coenzyme Q10, an antioxidant

Moderate long-term effects can include:

  • Increased liver enzymes and liver problems
  • Swelling
  • Muscle disease/weakness
  • Low white blood cells and low platelets
  • Weakness, numbness, and pain from nerve damage
  • Stomach problems such as inflammation and constipation
  • Impotence 
  • Diabetes 
  • Depression 
  • Lung tissue scarring

Severe long-term effects can include:

  • Chronic liver damage that can lead to liver failure
  • Muscle disease, weakness, and breakdown
  • Rhabdomyolysis
  • Inflamed pancreas 
  • Red blood cell destruction
  • Blood vessel inflammation
  • Lupus-like symptoms (fever, tiredness, and joint pain similar to symptoms of the autoimmune disease lupus)
  • Severe skin reactions that can be life-threatening

Report Side Effects

Zocor may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Zocor Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage forms (suspension or tablets):
    • For high cholesterol:
      • Adults—20 to 40 milligrams (mg) once a day in the evening. Your doctor may adjust your dose as needed.
      • Children 10 years of age and older—10 to 40 mg once a day in the evening. Your doctor may increase your dose as needed.
      • Children younger than 10 years of age—Use and dose must be determined by your doctor.


In some cases, your healthcare provider may modify your dose of Zocor.


Zocor has been studied in patients aged 10 to 17 years old. The people in the study were males or females who had a menstrual cycle for at least one year. The researchers looked at doses up to 40 mg in this age group. 

People in the study who took Zocor had similar side effects to those who took a placebo (an inactive pill). There were no significant effects on growth or sexual maturation, and no effect on the menstrual cycle in females. Sexually active adolescent females must use appropriate birth control while taking Zocor. 

Studies have not looked at the efficacy and safety of Zocor in children under 10 years and females who have not yet had their menstrual period. Because there is little data, most health professionals recommend delaying cholesterol-lowering drugs until the child is at least 8 to 10 years old, except in rare cases of severely high cholesterol. In these cases, the provider will carefully monitor growth and development.

Pregnancy and Breastfeeding

Notify your healthcare provider if you have become pregnant or plan to become pregnant while taking Zocor. Your provider will help determine whether you should stop taking the medication during pregnancy or temporarily stop statins while breastfeeding.

Older Adults

The safety and effectiveness of Zocor were similar in older and younger adults. However, some older adults can be more sensitive to the effects of Zocor. 

Adults aged 65 or older are at an increased risk for myopathy. Zocor should be used cautiously in this age group. Most older adults should take a maximum of 40 mg of Zocor per day.

People With Kidney Problems

Adults with severe kidney problems should start Zocor at the lowest dose of 5 mg once daily. Your healthcare provider will monitor you closely. Adults with mild to moderate kidney impairment do not require a lower dosage but should be monitored carefully.

Missed Dose

If you miss a dose of Zocor, take it as soon as you can. Skip the missed dose if it is almost time for the next dose. Do not take two doses together.

Overdose: What Happens If I Take Too Much Zocor?

If you take too much Zocor, you may have diarrhea, muscle pain, kidney failure, eye problems, or other reactions. In some cases, you may not have any symptoms. Do not take more Zocor than your healthcare provider tells you to.

What Happens If I Overdose on Zocor?

If you think you or someone else may have overdosed on Zocor, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses, has a seizure, has trouble breathing, or can’t wake up after taking too much Zocor, call 911 immediately.


Drug Content Provided and Reviewed by IBM Micromedex®

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it. Blood and urine tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

Do not use simvastatin if you are also taking boceprevir (Victrelis®), cobicistat-containing products (Stribild®), cyclosporine (Gengraf®, Neoral®, Sandimmune®), danazol (Danocrine®), gemfibrozil (Lopid®), nefazodone (Serzone®), telaprevir (Incivek®), certain antibiotics (eg, clarithromycin, daptomycin, erythromycin, itraconazole, ketoconazole, posaconazole, telithromycin, voriconazole, Nizoral®), or medicines to treat HIV/AIDS (eg, atazanavir, indinavir, nelfinavir, ritonavir, saquinavir, Crixivan®, Kaletra®, Lexiva®, Norvir®, Prezista®, Reyataz®). Using these medicines together with simvastatin may increase your risk of muscle injury and could result in kidney problems.

Chinese patients who are taking large amounts of niacin (greater than or equal to 1 gram or 1000 milligrams per day) together with this medicine may have an increased risk for muscle injury. Talk to your doctor if you are Chinese or have Chinese ancestry and take large amounts of niacin (Niacor®, Niaspan®). You may need a different dose of this medicine.

Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness, especially if you also have unusual tiredness or a fever. These may be symptoms of serious muscle problems, such as myopathy or immune-mediated necrotizing myopathy (IMNM). Myopathy is more common when high doses of simvastatin (eg, 80 milligrams) are used, but some people get myopathy with lower doses.

Call your doctor right away if you have dark-colored urine, diarrhea, a fever, muscle cramps or spasms, muscle pain or stiffness, or feel very tired or weak. These could be symptoms of a serious muscle problem called rhabdomyolysis, which can cause kidney problems.

Call your doctor right away if you get a headache, stomach pain, vomiting, dark-colored urine, loss of appetite, weight loss, general feeling of tiredness or weakness, light-colored stools, upper right stomach pain, or yellow eyes or skin. These could be symptoms of liver damage.

Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine if you have major surgery, a major injury, or you develop other serious health problems.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Zocor?

Zocor is not appropriate for everyone. Some people should not take Zocor. You should not take Zocor if you are allergic to simvastatin or any of the inactive ingredients.

Other reasons for not taking Zocor include:

  • Pregnancy
  • Breastfeeding 
  • Myopathy (muscle disease)
  • Liver disease 
  • Abnormal liver function test values on bloodwork (with no explanation)
  • If you take certain medicines known as CYP3A4 inhibitors, or gemfibrozil, danazol, or cyclosporine

Some people may or may not use Zocor and should check with their healthcare provider.

These include:

What Other Medications Interact With Zocor?

Certain drugs affect an enzyme that processes Zocor. This enzyme is called CYP3A4. Drugs that inhibit CYP3A4 cause higher levels of Zocor, which increases the risk of serious and life-threatening complications. You should not take Zocor with drugs that inhibit CYP3A4.

Some examples of these drugs and substances are:

  • Antifungals such as Sporanox (itraconazole), Duflucan (fluconazole), and Nizoral (ketoconazole)
  • Medications in the macrolide class of antibiotics such as erythromycin and clarithromycin
  • Certain human immunodeficiency (HIV) drugs
  • Grapefruit juice

Other drugs should not be taken with Zocor or should be prescribed with caution. These include:

  • Pacerone (amiodarone)
  • Norvasc (amlodipine)
  • Colcyrus (colchicine) 
  • Gengraf (cyclosporine)
  • Danocrine (danazol)
  • Cubicin (daptomycin)
  • Cardizem (diltiazem)
  • Tricor (fenofibrate)
  • Lopid (gemfibrozil)
  • Niaspan (niacin) 
  • Ranexa (ranolazine)
  • Veralan (verapamil)

What Medications Are Similar?

Other drugs in the statin class that work similar to Zocor include:

  • Crestor (rosuvastatin)
  • Lescol (fluvastatin)
  • Lipitor (atorvastatin)
  • Livalo (pitavastatin)
  • Mevacor (lovastatin)
  • Pravachol (pravastatin)

Other cholesterol drugs include:

  • Zetia (ezetimibe), which stops cholesterol from being absorbed in the small intestine
  • Vytorin (ezetimibe and simvastatin), which combines Zetia and Zocor to lower cholesterol 
  • PCSK9 inhibitors, such as Praluent (alirocumab) and Repatha (evolocumab)
  • Bile acid sequestrants, such as Welchol (colesevelam), Colestid (colestipol), and Questran (cholestyramine)
  • Caduet (atorvastatin and amlodipine), which contains a statin along with a calcium channel blocker
  • Fibrates such as Lopid (gemfibrozil) and the generic drug fenofibrate, which is available under several brand names such as Tricor, Lipofen, and Antara
  • Nexletol (bempedoic), which works by blocking cholesterol production in the liver
  • Niaspan (niacin), which blocks how your liver makes cholesterol
  • Omega-3 fatty acids such as Lovaza and Vascepa, which work by lowering fats and triglycerides in the liver

This is a list of drugs also prescribed for cholesterol. It is not a list of drugs recommended to take with Zocor. Ask your pharmacist or a healthcare provider if you have questions.

Frequently Asked Questions

  • What is Zocor used for?

    Zocor is a statin medication that contains the active ingredient simvastatin. Zocor is used, along with diet and exercise, to lower cholesterol.

  • How does Zocor work?

    Zocor blocks an enzyme, which slows down the production of cholesterol. Because less cholesterol builds up in the arteries, Zocor helps prevent problems such as heart attacks and strokes.

  • What drugs should not be taken with Zocor?

    Do not take Zocor with other drugs that inhibit an enzyme called CYP3A4. Some of these drugs include certain antifungals, antibiotics, and HIV drugs. Avoid grapefruit and grapefruit juice while taking Zocor. Before taking Zocor, consult your healthcare provider regarding all of the medicines, over-the-counter products, and nutritional supplements you take, so they can determine if Zocor is safe for you.

  • What are the side effects of Zocor?

    The most common side effects of Zocor are headache, upper respiratory infection, nausea, constipation, stomach pain, dizziness, eczema, diabetes, trouble sleeping, muscle pain, abnormal liver function tests, urinary tract infection, swelling, and problems with thinking and memory.

    Zocor can cause some serious side effects, too. Before taking Zocor, talk to your provider about what side effects to expect and how to address them.

  • How do I safely stop taking Zocor?

    Take Zocor every day, along with diet and exercise, as prescribed. Your provider will tell you if and when you can stop taking Zocor.

How Can I Stay Healthy While Taking Zocor

Before taking Zocor, discuss your medical conditions and medication history with your healthcare provider. Being open with your provider helps ensure that Zocor is prescribed safely. While taking Zocor, let your provider know when you start a new medication.

While taking Zocor, you can take steps to ensure you get the full benefits of your treatment. Follow your provider’s instructions for use and avoid drinking grapefruit and grapefruit juice while on the medication.

When you have high cholesterol, you usually feel fine and will not notice a difference in how you feel when you start taking Zocor. However, it is important to take Zocor to lower your cholesterol and prevent serious complications. Keep taking Zocor unless your provider tells you to stop. If you have serious side effects, check with a medical provider or get emergency medical help, if needed.

It can be difficult to remember to take your medicine for a condition with no symptoms. Setting a daily reminder on your phone can help you remember to take your medication every day. Using a weekly pill box can keep track of your pills. Call in your refills to the pharmacy a few days early to help prevent delays that can be caused if a medication is on order, or if the pharmacy needs to contact your prescriber.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare professional. Consult your doctor before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine. Medline Plus. Simvastatin.

  2. U.S. National Library of Medicine. DailyMed. Label: Zocor- simvastatin tablet, film coated.

  3. Prescribers’ Digital Reference. Drug Information. Zocor (simvastatin) - Drug summary.

  4. Epocrates. Zocor Entire Monograph.

  5. Food and Drug Administration. Zocor (simvastatin) tablets label.

By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.