When to avoid statins
Statins should not be taken if you have:
- liver disease
- persistently abnormal liver function blood tests
Before you start taking a statin, your doctor should ensure your liver function is normal. This involves carrying out a blood test to check for the liver enzyme (substance in the blood) serum transaminase.
This should be repeated one to three months after you start taking the statin and at six-month to one-year intervals while you are taking it. If the amount of serum transaminase in your blood rises to and stays at three times the upper limit of normal, your doctor will advise you to stop taking the statin.
Simvastatin
The statin called simvastatin should not be taken if you are taking medicines that slow down its breakdown by the liver. These include:
- some antibiotics (medicines for infection), including erythromycin, clarithromycin, itraconazole and ketoconazole
- some medicines for HIV (human immunodeficiency virus) infection, including indinavir, lopinavir, ritonavir and saquinavir
If you take these medicines and also need treatment for high cholesterol, you may take one of the other statins.
Pregnancy and breastfeeding
Statins should not be taken by women who are pregnant or breastfeeding.
Using statins with caution
Statins should be taken with caution if you have risk factors for developing the rare side effects of myopathy and rhabdomyolysis (types of muscle disorder that cause muscle pain and breakdown of muscle tissue). These risk factors include:
- being over 70 years old
- having a history of liver disease
- drinking large quantities of alcohol
- having a history of muscle side effects when taking a statin or fibrate (another type of medicine for high cholesterol)
- having a family history of myopathy (muscle damage) or rhabdomyolysis (kidney damage caused by a substance called myoglobin that is released into the blood when your muscles are inflamed or damaged)
If you have an underactive thyroid, only take a statin if your thyroid problem is being treated and is under control.
