The medicine is available on prescription as tablets. You can also buy a low-strength 10mg tablet from a pharmacy.
- 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.
- Don't take simvastatin if you're pregnant or think you might be pregnant. This medicine can harm an unborn baby.
- Don't drink grapefruit juice while you're taking simvastatin. It doesn't mix well with this medicine.
- Simvastatin is also called Zocor and Simvador.
Who can and can't take simvastatin
Simvastatin can be taken by adults and children over the age of 10.
Simvastatin isn't suitable for some people. Tell your doctor if you:
- have had an allergic reaction to simvastatin or any other medicines in the past
- 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
How and when to take
Take simvastatin once a day in the evening.
Simvastatin doesn't upset the stomach, so you can take it with or without food.
How much will I take?
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.
The usual starting dose in children is 10mg each evening. Your child's doctor might increase this after 4 weeks. The maximum dose in children is 40mg.
Your dose depends on the reason for taking it, your cholesterol levels, and what other medicines you're taking.
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 forget doses often, 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 by accident is unlikely to harm you.
Talk to your pharmacist or doctor if you're worried or you take more than 1 extra dose.
Simvastatin seems to be a very safe medicine. It's unusual to have side effects.
One rare but serious side effect is unexplained muscle pain, tenderness or weakness. This is more likely if you're taking a higher dose of simvastatin. Talk to your doctor or pharmacist is the side effects bother you or don't go away.
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 tell a doctor if you get:
- muscle pain, tenderness, weakness or cramps - these are signs of muscle breakdown and kidney damage
- yellow skin or eyes - this is 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 tummy pain - this is a sign of pancreas problems
- a cough, feeling short of breath, and weight loss - this is a sign of lung disease
Serious allergic reaction
In rare cases, it’s possible to have a serious allergic reaction to simvastatin.
A serious allergic reaction is an emergency. Contact a doctor straight away if you think you or someone around you is having a serious allergic reaction.
The warning signs of a serious allergic reaction are:
- getting a skin rash that may include itchy, red, swollen, blistered or peeling skin
- tightness in the chest or throat
- having trouble breathing or talking
- unusual hoarseness
- swelling of the mouth, face, lips, tongue, or throat
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 to the UK safety scheme.
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.
Cautions with other medicines
Some medicines don't mix well with simvastatin including:
- some antibiotics and antifungals
- some HIV medicines
- some hepatitis C medicines
- warfarin (stops blood clotting)
- ciclosporin (treats psoriasis and rheumatoid arthritis)
- danazol (treats endometriosis)
- nefazodone (treats depression)
- amiodarone (makes your heart stable)
- verapamil, diltiazem, amlodipine (for high blood pressure and heart problems)
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 doesn't 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.
How does simvastatin work?
Are statins safe?
Is simvastatin addictive?
How long will I take simvastatin for?
Can I take simvastatin for a long time?
Are there other cholesterol-lowering medicines?
Is there any food or drink I need to avoid?
Can I drink alcohol with it?
Can I drive or ride a bike?
Will it affect my contraception?
Will it affect my fertility?
What will happen when I come off simvastatin?
Can lifestyle changes help?