Easy-to-read medicine information about statins – what they are, how to take statins safely and possible side effects.

On this page, you can find the following information:

Statins are a group of medicines used to lower cholesterol (or lipids) in your blood. Having high cholesterol can cause fatty deposits in your blood vessels (atherosclerosis) and increase your chance of having a heart attack, stroke or coronary artery disease.

Which statins are available in New Zealand?

How do statins work?

Statins slow down the production of cholesterol in your liver. 

  • Cholesterol is measured in mmol/L.
  • Having a total cholesterol above 4 mmol/L increases your chance of having atherosclerosis.
  • If you have high cholesterol, even lowering it by 1 mmol/L will lower your risk of a fatal heart attack or stroke by 20%.
  • The longer you take a statin, the more you reduce your risk of a heart attack or stroke. 

Read more about high cholesterol

When are statins used?

Statins are used if you are at risk of having a stroke or heart attack – this is checked at a cardiovascular or heart risk assessment

Cardiovascular risk Treatment recommendations
Cardiovascular risk lower than 10%
  • Make healthy lifestyle decisions.
  • Most people will not need cholesterol-lowering medicines
Cardiovascular risk 10 to 20%
  • Make healthy lifestyle changes and discuss the benefits and risks of medicines with your doctor.
  • If after 6 to 12 months of lifestyle changes your cardiovascular risk has not reduced, then a statin may be considered
Cardiovascular risk greater than 20% 


You have a cardiovascular condition


You've had a stroke or heart attack in the past 
  • Lipid-lowering medicines are recommended plus healthy lifestyle changes

Your dose of statin will depend on your cardiovascular risk – people with a lower cardiovascular risk will be on lower doses compared with people at higher risk.

What are the benefits of taking statins?

Statins reduce cardiovascular risk by reducing LDL cholesterol (often called bad cholesterol).

  • In people who have high LDL cholesterol level (≥4 mmol/L), statins can reduce LDL cholesterol by more than half.
  • Reducing LDL cholesterol can help to reduce heart attacks and strokes.
  • Every 1 mmol/L decrease in LDL cholesterol reduces major vascular events by approximately 25% and fatal heart attack or stroke by 20%.

Are there any risks with taking statins?

Most people have few, if any, side effects from statins. The most common side effects are tummy upset such as indigestion, bloating, flatulence (wind), headache, and stuffy nose.

Some people may have:

  • muscle pain or weakness (called myopathy, see below)
  • an increased risk of developing type 2 diabetes (see below)
  • an increased risk of stroke caused by a bleed in the brain; however, there is also a lower risk of stroke caused by a blocked blood vessel. These risks are thought to balance each other out. 

There are also reports that statins may affect cognitive function, mainly memory loss and confusion, and affect sleep and mood but these have not been fully proven. 

Muscle pain or weakness

Some people will have muscle pain or weakness when taking statins. This is rarely serious and often goes away with time. If your pain is severe, sudden or comes on shortly after you start your statin see your doctor.

Your doctor will check an enzyme called creatine kinase to see if the aches and pains are possibly being caused or made worse by the statins. If so:

  • a lower dose or a different statin may be prescribed, or
  • you may choose to continue living with the aches because of the benefits of the statin, or
  • you may discuss stopping taking your statin with your doctor.

Your doctor will also want to check for a rare but serious condition called rhabdomyolisis and will check any other medicines you are taking. Rhabdomyolisis can be caused by an interaction between statins and some other medicines including antibiotics.

Increased risk of type 2 diabetes

There is a small chance that statins may increase your risk of getting type 2 diabetes. However, it is usually recommended that people at risk of diabetes do take statins if they are needed to help lower their cholesterol. This is because the overall benefit in terms of health and wellbeing of taking statins and preventing a heart attack or stroke is seen to be greater than the consequences of developing diabetes.

What should I consider when deciding if I should start treatment with a statin?

The balance of benefit and risk will differ for each person.

  • For example, people at the highest cardiovascular risk will benefit the most from taking a statin. Any possible side effects from statins are likely to be thought of as a lower risk.
  • On the other hand, people at a lower level of cardivascular disease risk will have less benefit from taking a statin but have the same risk of side effects. Therefore they may feel that the risk of taking a statin outweighs the benefit.

Your doctor will discuss your cardiovascular risk with you, any possible side effects and how these could affect you.

How will my doctor know I am at high risk of heart disease?

By doing a cardiovascular or heart risk assessment your GP will build up a picture of your risk profile. This involves examining your family health history, age, weight and smoking history and diabetes status, and then testing indicators including your cholesterol levels and blood pressure. Your GP may use a computerised tool called Predict to calculate your risk. This will give you a percentage risk of developing vascular disease and can even track your potential progress as you age.

What other ways could I lower my cholesterol?

Eating a healthy diet, exercising regularly and drinking no more than one alcoholic drink a day have all been shown to improve your cholesterol levels. It is best to eat a low-fat diet, and reduce the amount of saturated fat you eat.

Read more about ways to reduce your cholesterol

Once I start using statins will I be on them forever?

Yes, most people will need to keep taking their statin. The benefits of reducing your risk of having a stroke or heart attack will only continue for as long as you take it. If you stop taking the statin without starting a different cholesterol-lowering treatment, your cholesterol level may rise again.

Which medications or foods do statins interact with?

Some medicines and foods affect the way your liver can process the statin, increasing the risk of side effects. Grapefruit is a common food that has this effect with statins. Having large quantities of grapefruit while taking simvastatin or atorvastatin can increase your risk of side effects. But, eating one serving of marmalade, no more than half a grapefruit or drinking no more than a standard glass (250 mL) of grapefruit juice each day, should not be a problem if you are taking statins. It's best to allow 12 hours between having these foods and taking your statin dose, so if you take your statin in the evening have your grapefruit in the morning

Statins interact with a few other medicines, including some antibiotics so it is important that you check with your doctor before taking any new medicines.

Learn more

Frequently asked questions (FAQs) about statins
Heart Foundation, NZ


  1. Prescribing statins to reduce cardiovascular risk BPAC, 2017
  2. Investigating myalgia in patients taking statins BPAC, 2014

Additional resources for healthcare professionals

Webinar – statins — who, when, where and why Goodfellow Unit, NZ, 2017

Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 17 Jan 2018