What are statin side effects?

Muscle pain and damage

One of the most common complaints of people taking statins is muscle pain. You may feel this pain as a soreness, tiredness, or weakness in your muscles. The pain can be a mild discomfort, or it can be serious enough to make it hard to do your daily activities.

However, researchers have found a "nocebo effect" when it comes to people thinking they have muscle pain from statins. A nocebo effect means people who expect a negative side effect from a medicine report experiencing the potential side effect at higher rates than the medicine should cause.

The real risk of developing muscle pain from taking statins is about 5% or less compared with taking a placebo. A placebo is a pill that doesn't contain medicine. Studies have found that people stopped taking the pills because of muscle aches even when they were taking a placebo. A strong predictor of if you'll experience muscle aches when taking statins could be whether you read about the potential side effect.

Very rarely, statins can cause life-threatening muscle damage called rhabdomyolysis (rab-doe-my-OL-ih-sis). Rhabdomyolysis can cause extreme muscle pain, liver damage, kidney failure, and death. The risk of very serious side effects is extremely low. Only a few cases of rhabdomyolysis occur per million people taking statins. Rhabdomyolysis can occur when you take statins in combination with certain medicines or if you take a high dose of statins.

Liver damage

Sometimes, statin use could cause an increase in the level of enzymes in the liver. These enzymes signal inflammation. If the increase is only mild, you can continue to take the statin. Rarely, if the increase is severe, you may need to try a different statin.

Although liver problems are rare, your healthcare team may order a liver enzyme test before or shortly after you begin to take a statin. You won't need any further liver enzyme tests unless you begin to have signs of trouble with your liver.

Contact your healthcare professional right away if you have unusual fatigue or weakness, loss of appetite, pain in your upper stomach, dark-colored urine, or yellowing of your skin or eyes.

Increased blood sugar or type 2 diabetes

It's possible that your blood sugar, known as blood glucose, may increase when you take a statin. This may lead to type 2 diabetes. The risk is small but important enough that the U.S. Food and Drug Administration (FDA) has issued a warning on statin labels about blood glucose levels and diabetes.

The increase in blood sugar is small. And it does not cause concern unless it occurs when blood sugar levels are already high. People with prediabetes or diabetes may be more aware that their blood sugar levels rise when they start taking a statin.

But statins also prevent heart attacks in people with diabetes. The benefit of taking statins likely outweighs the small risk to have the blood sugar level go up. Talk to your healthcare team if you have concerns.

Neurological side effects

The FDA warns on statin labels that some people have developed memory loss or confusion while taking statins. These side effects reverse once you stop taking the medicines. There is limited evidence to prove a cause-effect relationship, and several studies have found that statins have no effect on memory. Talk to your care team if you experience memory loss or confusion while taking statins.

There also has been evidence that statins may help with brain function — in people with dementia, for example. This is still being studied. Don't stop taking your statin medicine before talking to your healthcare professional.