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.
- Take 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 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 an allergy to simvastatin
- 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 had muscular side effects when taking a statin in the past
- 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.
The usual dose 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.
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.
Your dose depends on the reason for taking it, your cholesterol levels, and what other medicines you're taking.
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 that are suitable for you and your medicines.
What if I take too much?
Accidentally taking an extra dose of simvastatin is unlikely to harm you.
Talk to your pharmacist or doctor if you're worried or you take more than one 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.
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 develop:
- muscle pain, tenderness, weakness or cramps (signs of muscle breakdown and kidney damage)
- yellowing of the skin and eyes, dark-coloured pee or pale-coloured poo, itching, feeling tired or weak, and loss of appetite (warning signs of liver problems)
- severe tummy pain (a sign of inflammation of the pancreas)
- a cough, feeling short of breath, and weight loss (signs of interstitial lung disease)
Serious allergic reaction
The warning signs of a serious allergic reaction are:
- a skin rash that may include itchy, red, swollen, blistered or peeling skin
- tightness in the chest or throat
- trouble breathing or talking
- swelling of the mouth, face, lips, tongue or throat
Pregnancy and breastfeeding
Simvastatin is not recommended in pregnancy and while breastfeeding as there's no firm evidence that it's safe.
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.
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 conditions)
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 the 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?