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Simvastatin belongs to a group of medicines known as statins. It regulates the amount of cholesterol and other lipids made by your body, and helps to reduce the risk of heart and blood vessel disease.

Take one dose each evening.

Follow carefully any lifestyle advice you have been given such as stopping smoking, avoiding drinking too much alcohol, eating a healthy diet and taking exercise. These also help to reduce the risk of heart and blood vessel disease.

Do not drink grapefruit juice.

If you develop any unusual cramps or pains in your muscles, contact your doctor for advice as soon as possible.

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About simvastatin

Type of medicine

A lipid-regulating medicine commonly known as a statin

Used for

Lowering cholesterol and other lipids in the blood; to reduce the risk of heart and blood vessel disease

Also called


Combination brand: Inegy® (simvastatin with



Available as

Tablets and oral liquid medicine

Lipids, or fats, are made naturally in your body from the food you eat. They are easily stored in your body and serve as a source of energy. Cholesterol and triglycerides are types of lipid. If the concentration of these lipids in your blood becomes too high, it leads to a condition called hyperlipidaemia. If it is the concentration of cholesterol which has become too high, it is called hypercholesterolaemia. Although a high blood concentration of lipids will not make you feel ill, it can cause a problem if it is left untreated.

People with high lipid levels can develop small fatty patches called atheroma. These patches develop when excess fat is deposited on to the walls of blood vessels. Over time, these patches can make a blood vessel narrower and this is called atherosclerosis (sometimes referred to as 'hardening of the arteries'). The narrowing reduces the blood flow through the artery and increases the risk of a number of heart and blood vessel diseases, such as heart attack and stroke.

Simvastatin belongs to a group of medicines known as statins (or HMG-CoA reductase inhibitors). It regulates the amount of cholesterol and other lipids made by your body. It does this by blocking the action of a certain enzyme (called HMG-CoA reductase) which your body needs to make the fats. This lowers your risk of heart and blood vessel disease. It can also reduce this risk, even if your cholesterol levels are normal, if you are at an increased risk of heart disease as a result of other healthcare problems (such as if you have diabetes mellitus).

Before taking simvastatin

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking simvastatin it is important that your doctor knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you have any problems with the way your liver works, or if you have ever had a disease which has affected your liver.

  • If you have an underactive thyroid gland.

  • If you have a problem with unexplained muscle aches or pains, or if you (or a close relative) have ever had a muscle disorder.

  • If you regularly drink large amounts of alcohol.

  • If you have any problems with the way your kidneys work.

  • If you have ever had an allergic reaction to a medicine.

  • If you are taking any other medicines. This is particularly important because there are a number of medicines that should not be taken with simvastatin, and there are also some medicines that will affect the dose of simvastatin that your doctor prescribes for you. Please also make sure that your doctor knows of any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

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How to take simvastatin

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about simvastatin and will provide you with a full list of the side-effects which you may experience from taking it.

  • Take one dose of simvastatin each day, in the evening. There are several different strengths of tablet available (10 mg, 20 mg, 40 mg and 80 mg) - your doctor will tell you which strength of tablet is right for you. Swallow the tablet with a drink of water. If you have any difficulties swallowing, let your doctor know about this as a liquid medicine may be more suitable for you.

  • You can take simvastatin before or after food.

  • Do not drink grapefruit juice at any time while you are taking simvastatin. This is because a chemical in grapefruit juice increases the amount of simvastatin in your bloodstream. This makes side-effects more likely and increases the risk of them being more serious.

  • If you forget to take a dose, leave out the missed dose but make sure that you remember to take your next dose on the following evening. Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor. This is so that your doctor can check on your progress. You will need to have some blood tests from time to time. These are to measure your lipid levels and also to check that your liver has not been affected by taking simvastatin.

  • Your doctor will give you advice about eating a healthy diet, cutting down on the amount of alcohol you normally drink, reducing the amount of salt in your diet, stopping smoking, and taking regular exercise. Following this advice will also help you to reduce your risk of developing heart and blood vessel disease.

  • Women taking simvastatin must avoid getting pregnant. Make sure you have discussed with your doctor which types of contraception are suitable for you and your partner.

  • Treatment with simvastatin is usually long-term unless you experience an adverse effect. You should continue to take it regularly.

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Can simvastatin cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the side-effects associated with simvastatin, although these tend to occur only rarely and are usually mild in nature. You will find a full list in the manufacturer's information leaflet supplied with your medicine. Unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Simvastatin side-effects (these affect fewer than 1 in 1,000 people)

What can I do if I experience this?

Muscle cramp, pain or tenderness

Although this may not be anything to be concerned about, you should tell your doctor about this. This is because there is a rare but serious side-effect of simvastatin which is a severe form of muscle inflammation


Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know

Feeling sick (nausea), indigestion, wind (flatulence), stomach upset

Stick to simple meals - avoid rich or spicy food

Feeling dizzy or tired, tingling feelings, itchy rash, hair thinning

Speak with your doctor if any of these become troublesome

Important: simvastatin has been associated with some more serious side-effects in a very few people. Although these occur only rarely, it is important that you tell your doctor straightaway if you experience any of the following symptoms:

  • If you develop any muscle cramps or pains, particularly if they are in your legs and you also feel unwell or have a high temperature (fever).

  • If you feel short of breath or develop an unexplained cough. This is because (in very rare cases) statin medicines like simvastatin can cause a disease called interstitial lung disease.

  • If you develop any allergic-type reactions, such as swelling around your mouth or face, or a skin rash.

If you experience any other symptoms which you think may be due to simvastatin, speak with your doctor or pharmacist for further advice.

How to store simvastatin

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

  • The oral liquid medicine may be used for one month once the bottle has been opened. After this time, get a fresh supply.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.

If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

MHRA - Reporting adverse reactions

Report suspected side effects to medicines, vaccines, e-cigarettes, medical device incidents, defective or falsified (fake) products to the Medicines and Healthcare products Regulatory Agency to ensure safe and effective use.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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