Heart Health
Statins: Benefits, Side Effects, and Common Questions
A simple guide to why statins are prescribed, how they protect the heart and brain, and what to watch for.
Patient information page | Last reviewed: June 2026
The quick answer
Statins are medicines that lower LDL cholesterol, often called bad cholesterol. They reduce the risk of heart attack and stroke, especially in people who already have cardiovascular disease or who have a higher future risk.
Most people tolerate statins well. Some people notice side effects such as muscle aches or stomach upset, but serious side effects are uncommon. If a statin does not suit you, your doctor may be able to adjust the dose, change the statin, or discuss another treatment option.
Statins at a glance
Lower LDL
They reduce harmful cholesterol made by the liver.
Protect arteries
They reduce the chance of fatty plaques causing trouble.
Often tolerated
Many people take them long term without difficulty.
Report symptoms
Muscle pain or weakness should be discussed with a doctor.
Do not stop suddenly
Ask for advice, especially after heart attack or stroke.
What are statins?
Statins are a group of medicines that reduce how much cholesterol the liver makes. They work by blocking an enzyme involved in cholesterol production.
Common examples
Atorvastatin, rosuvastatin, simvastatin, and pravastatin are common statins.
Main effect
Statins mainly lower LDL cholesterol. They can also lower non-HDL cholesterol and, in some people, mildly reduce triglycerides.
Why has my doctor recommended a statin?
Doctors usually recommend statins for one of two reasons.
Primary prevention
This means reducing the chance of a first heart attack or stroke in someone who has not yet had one, but whose overall risk is raised. Your doctor may consider age, cholesterol, blood pressure, diabetes, smoking, kidney disease, family history, and other risk factors.
Secondary prevention
This means reducing the chance of another event in someone who already has cardiovascular disease, such as previous heart attack, angina, stroke or mini-stroke, peripheral artery disease, stent, or bypass surgery.
How do statins help?
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They lower LDL cholesterol. LDL cholesterol can enter artery walls and contribute to fatty plaque build-up. Lowering LDL reduces the chance of these plaques causing future problems.
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They reduce heart attack and stroke risk. By lowering harmful cholesterol particles, statins reduce the risk of blocked arteries in the heart and brain.
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They help stabilise existing plaques. If fatty plaques are already present, statins can make them less likely to rupture. A ruptured plaque can trigger a sudden blood clot, which may cause a heart attack or stroke.
Possible side effects
Like all medicines, statins can cause side effects, but many people take them without difficulty.
Muscle aches or weakness
Some people notice muscle aching, tenderness, heaviness, cramps, or weakness. This can happen for many reasons, and it is not always caused by the statin. If symptoms are mild, do not stop suddenly without advice. Speak to your doctor.
Stomach symptoms
Some people notice nausea, wind, diarrhoea, constipation, or tummy discomfort when starting treatment. These symptoms are often mild and may settle.
Liver blood test changes
Statins can sometimes affect liver enzyme blood tests. Serious liver injury is rare, but your doctor may check liver blood tests before or after starting treatment.
Blood sugar
Statins can slightly increase blood sugar in some people. For people at high risk of heart attack or stroke, the heart and brain protection usually outweighs this small risk.
Common questions
Do I have to take a statin at night?
It depends on the statin. Some shorter-acting statins, such as simvastatin, are usually taken in the evening. Longer-acting statins, such as atorvastatin and rosuvastatin, can often be taken at any time of day. Follow the instructions on your prescription.
Can I eat grapefruit?
Grapefruit and grapefruit juice can interact with some statins, especially simvastatin and atorvastatin. Check the patient leaflet or ask your doctor or pharmacist whether grapefruit is safe with your specific medicine.
Will I need to take a statin forever?
Many people take statins long term, especially after heart attack, stroke, stent, bypass surgery, or if cardiovascular risk is high. The decision should be reviewed with your doctor if your risk changes, side effects occur, or treatment goals change.
Can lifestyle changes replace a statin?
Lifestyle changes are important for everyone. For some people with mildly raised cholesterol and low overall risk, they may be enough. For people with high risk or previous cardiovascular disease, lifestyle changes and statins often work best together.
Pregnancy and breastfeeding
Statins are usually avoided during pregnancy and breastfeeding. Tell your doctor if you are pregnant, planning pregnancy, or breastfeeding.
Do not stop suddenly without advice
If you think your statin is causing side effects, speak to your doctor. They may suggest checking a blood test, reducing the dose, trying a different statin, or reviewing other possible causes. Do not stop a statin suddenly without medical advice, especially if you have had a heart attack, stroke, stent, bypass surgery, or another cardiovascular condition.
When to get urgent help
Seek urgent medical help if you develop severe unexplained muscle pain or weakness, muscle symptoms with fever or feeling very unwell, dark brown urine, yellowing of the skin or eyes, severe upper abdominal pain, or symptoms of an allergic reaction such as swelling of the lips, tongue, or throat, or breathing difficulty.
Key message
Statins are used to lower harmful cholesterol and reduce the risk of heart attack and stroke. Most people tolerate them well, and side effects can often be managed by adjusting the dose or changing the statin.
Do not stop a statin suddenly without medical advice, especially if you have had a heart attack, stroke, stent, bypass surgery, or another cardiovascular condition.
References
- NHS. Statins.
- NHS. Statins: side effects and considerations.
- British Heart Foundation. Statins: your questions answered.
- American Heart Association. Statin safety and cholesterol guidance.
- Mayo Clinic. Statin side effects: weighing benefits and risks.