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  1. About simvastatin
  2. Key facts
  3. Who can and cannot take simvastatin
  4. How and when to take simvastatin
  5. Side effects
  6. Pregnancy and breastfeeding
  7. Cautions with other medicines
  8. Common questions

1. About simvastatin

Simvastatin belongs to a group of medicines called statins.

It's used to lower cholesterol if you've been diagnosed with high blood cholesterol. It's also taken to prevent heart disease, including heart attacks and strokes.

Your doctor may prescribe simvastatin if you have a family history of heart disease, or a long-term health condition such as rheumatoid arthritis, or type 1 or type 2 diabetes.

The medicine is available on prescription as tablets. You can also buy a low-strength 10mg tablet from a pharmacy.

2. Key facts

  • Simvastatin seems to be a very safe medicine. It's unusual to have any side effects.
  • Keep taking simvastatin even if you feel well, as you will still be getting the benefits. Most people with high cholesterol don't have any symptoms.
  • Do not take simvastatin if you're pregnant, trying to get pregnant or breastfeeding.
  • Do not drink grapefruit juice while you're taking simvastatin. It doesn't mix well with this medicine.
  • Simvastatin is also called Zocor and Simvador.

3. Who can and cannot take simvastatin

Simvastatin can be taken by adults and children over the age of 10 years.

Simvastatin is not suitable for some people. Tell your doctor if you:

  • have ever had an allergic reaction to simvastatin or any other medicine
  • have liver or kidney problems
  • are trying to get pregnant, think you might be pregnant, you're already pregnant, or you're breastfeeding
  • have severe lung disease
  • regularly drink large amounts of alcohol
  • have an underactive thyroid
  • have, or have had, a muscle disorder (including fibromyalgia)

4. How and when to take simvastatin

Take simvastatin once a day in the evening. This is because your body makes most cholesterol at night.

Simvastatin doesn't upset the stomach, so you can take it with or without food.


The usual dose for adults is between 10mg and 40mg once a day. People with very high cholesterol levels may be prescribed a higher dose of 80mg a day.

Your dose depends on the reason for taking it, your cholesterol levels, and what other medicines you're taking. Ask your doctor or pharmacist for advice if you're unsure how much to take. Do not reduce your dose without talking to your doctor first.

The usual starting dose in children is 10mg each evening. Your child's doctor might increase this after 4 weeks. The dose is based on your child's age, going up to a maximum of 40mg.

How to take it

Swallow simvastatin tablets whole with a glass of water.

There's some evidence simvastatin works better at lowering cholesterol if you take it in the evening rather than in the morning.

What if I forget to take it?

If you occasionally forget to take a dose, take your next dose the next day at the usual time. Never take 2 doses at the same time. Never take extra doses.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

What if I take too much?

Taking an extra dose of simvastatin is unlikely to harm you.

Talk to your pharmacist or doctor if you're worried or if you take more than 1 extra dose.

5. Side effects

Simvastatin seems to be a very safe medicine and it's unusual to have side effects. However, different statins can affect people in different ways.

Talk to your doctor or pharmacist if side effects bother you or don't go away. They may recommend taking a different statin.

One rare but serious side effect is unexplained muscle aches and pains. This is more likely if you're taking a higher dose of simvastatin - and it can happen a few weeks or months after you first start taking this medicine. Report any unexplained muscle pain, tenderness or weakness to a doctor straight away.

Another very rare side effect can be memory loss. This usually goes away when you stop taking the medicine.

Serious side effects

It happens rarely, but less than 1 in 1,000 people taking simvastatin may have a serious side effect.

Stop taking simvastatin and call a doctor if you get:

  • muscle pain, tenderness, weakness or cramps – these can be signs of muscle breakdown and kidney damage
  • yellow skin or the whites of your eyes turn yellow, or if you have pale poo and dark pee – this can be a sign of liver problems
  • a skin rash with pink-red blotches, especially on the palms of the hands or soles of the feet
  • severe stomach pain – this can be a sign of pancreas problems
  • a cough, feeling short of breath, and weight loss – this can be a sign of lung disease

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to simvastatin.

Immediate action required: Call 999 or go to A&E now if:
  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

You could be having a serious allergic reaction and may need immediate treatment in hospital.

These are not all the side effects of simvastatin. For a full list see the leaflet inside your medicines packet.


You can report any suspected side effect using the Yellow Card safety scheme.

Visit Yellow Card for further information.

6. Pregnancy and breastfeeding

Simvastatin is not recommended in pregnancy and while breastfeeding.

Talk to your doctor if you're planning to become pregnant. It's best to stop taking simvastatin at least 3 months before you start trying for a baby.

If you become pregnant while taking simvastatin, stop taking the medicine and tell your doctor.

Simvastatin and breastfeeding

It's not known if simvastatin passes into breast milk, but it may cause problems for your baby. You may be able to stop taking simvastatin temporarily while you breastfeed.

Non-urgent advice: Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

7. Cautions with other medicines

Some medicines don't mix well with simvastatin, including:

If you're taking simvastatin and need to take one of these medicines, your doctor may:

  • prescribe a lower dose of simvastatin
  • prescribe a different statin medicine
  • recommend that you temporarily stop taking your simvastatin

Mixing simvastatin with herbal remedies and supplements

St John's wort, a herbal medicine taken for depression, reduces the amount of simvastatin in your blood, so it does not work as well.

Talk to your doctor if you're thinking about starting St John's wort, as it will change how well simvastatin works.

Important: Medicine safety

Tell your doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.

8. Common questions

How does simvastatin work?

Simvastatin acts on the liver to stop it making cholesterol. This lowers your blood cholesterol level.

For the first 12 months on this medicine, you'll be offered a couple of routine tests to make sure your liver is working OK.

How long do statins take to work?

Your cholesterol levels should drop noticeably within 4 weeks – if you take your medicine regularly, as prescribed.

How long will I take simvastatin for?

Usually, treatment with a statin such as simvastatin is for life. The benefits will only continue for as long as you take it. If you stop taking simvastatin without starting a different treatment, your cholesterol level may rise again.

Are statins safe?

You may have read negative stories about statins, but they're thought to be very safe, effective medicines.

Statins are thought to have very few side effects. Sometimes the side effects that people report aren't related to their medicine. However, if you're concerned about the safety of statins, talk to your doctor.

Is it safe to take simvastatin for a long time?

Simvastatin is safe to take for a long time. In fact, it works best if you take it for a long time.

Statins have been used for nearly 30 years to lower cholesterol.

Is simvastatin addictive?

No, there's no evidence that simvastatin is addictive. You will not get any withdrawal symptoms when you stop taking it.

What will happen if I come off it?

You may want to stop simvastatin if you think you're having side effects.

Talk to your doctor first to see if it really is a side effect of simvastatin or an unrelated problem. Your doctor may decide to lower your dose or change your medicine.

You will not get any withdrawal symptoms. However, stopping simvastatin may cause your cholesterol to rise. This increases your risk of heart attacks and strokes.

If you want to stop taking your medicine, it's important to find another way to lower your cholesterol.

Does it help to take supplements together with statins?

There's some interest in taking CoQ10 together with statins. However there's no firm evidence that taking CoQ10 at the same time as simvastatin will benefit your health. More research is needed.

If you decide to take a CoQ10 supplement, tell your doctor or pharmacist. Supplements can interfere with other medicines you may also be taking.

Will taking pravastatin increase my risk of diabetes?

If you're at high risk of developing type 2 diabetes, taking statins may slightly increase this risk. This is because statins can raise your blood sugar a little.

Speak to your doctor, who will be able to explain how the benefits of taking statins are likely to outweigh this small increased risk.

If you already have type 2 diabetes, your doctor may advise monitoring your blood sugar levels more closely for the first few months. Tell your doctor or diabetes nurse if you find it harder to control your blood sugar.

How does it compare with other medicines for high cholesterol?

Statins all work in the same way, but they differ in how well they lower cholesterol.

There are several other statin medicines for lowering your cholesterol, including:

If you have a side effect with one statin, it may not happen with another. Some medicines don't mix well with one statin, but you can take them with a different one.

Your doctor will find the right statin and dose for you, depending on your medical history, cholesterol level and the other medicines you take.

Can I drive or ride a bike?

Occasionally, simvastatin can make you feel dizzy. If this happens to you, do not drive, cycle or use machines or tools until you feel better.

Will it affect my fertility?

There's no clear evidence to suggest that taking simvastatin will reduce fertility in either men or women.

However, speak to a pharmacist or your doctor before taking it if you're trying to get pregnant.

Will it stop my contraception working?

Simvastatin won't affect any type of contraception, including the combined pill and emergency contraception.

Can I drink alcohol with it?

Yes, you can drink alcohol while taking simvastatin.

However, drinking a lot of alcohol may increase the chances of you getting muscle and liver side effects.

Try to keep to the recommended guidelines of no more than 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.

Is there any food or drink I need to avoid?

Do not drink grapefruit juice if you're taking simvastatin. It increases the concentration of simvastatin in your system.

Can lifestyle changes help?

Reducing your cholesterol may mean you don't need to be prescribed a statin medicine. There are lifestyle changes you can make that will help lower your cholesterol:

Page last reviewed: 20 December 2018
Next review due: 20 December 2021