Statins don’t cause most of the side effects listed on their labels

The long list of side effects associated with statins is vastly overstated, according to the most rigorous assessment of the evidence to date. This is prompting calls for the drugs’ packaging to be updated, over concerns that warnings regarding these supposed side effects are putting people off the life-saving medicines.

“We can now be confident that statins do not cause the vast majority of medical issues listed as potential side effects in statin patient information leaflets,” said Christine Reith at the University of Oxford at a press briefing on 3 February.

Statins, which lower cholesterol levels, are inexpensive drugs that significantly cut the risk of heart attacks and strokes. But there has long been concern surrounding their supposed side effects, namely muscle pain, despite a study in 2022 showing that this is rarely caused by statins.

“Unfortunately, ongoing confusion and concern – not just in patients, but also many doctors regarding potential statin side effects – mean that many people are not willing to start statins or stop [taking] them,” said Reith.

Now, Reith and her colleagues have looked into the side effects that are commonly listed on statin labels, such as dizziness, fatigue, memory loss and headache, which normally end up there following evidence from case reports and observational studies. They didn’t investigate muscle pain or weakness, or whether there is an increased risk of diabetes, which was flagged as a small risk in a previous analysis.

The researchers analysed 19 randomised controlled trials, involving 120,000 participants who were followed for 4.5 years, on average, looking into the effects of five of the most commonly prescribed statins relative to a placebo.

Of the 66 side effects they analysed, they found that statins don’t seem to be the cause for the vast majority of them, with similar rates of incidence occurring in the placebo groups. They may arise due to the nocebo effect, where the expectation of harm leads to someone experiencing it, says Jeffrey Berger at New York University Langone Health.

The researchers did find that statins legitimately raise the risk of a few side effects, such as excess protein levels in urine, limb swelling and changes in liver function, but not to the extent that they seem to cause harm. “This allows us to be confident in saying that the benefits of statins really do significantly outweigh their risks,” said Reith.

Drug regulators should now update statin labels, says Karol Watson at the University of California, Los Angeles. For instance, labels could make clear which side effects are actually caused by statins and which seem to occur at similar rates among people on a placebo, she says.

But this is rarely a quick process – the UK’s Medicines and Healthcare Products Regulatory Agency only recommended that statin labels update descriptions of muscle weakness and pain as a side effect in January 2026, for instance.

In the meantime, clinicians can use the results to reassure people who are taking statins, or who could benefit from them. “It’s not about telling people that they’re crazy, that they’re wrong or you don’t have a side effect, it’s about educating them to change their expectations and help them,” says Berger.

Watson hopes the review will settle the debate around statin side effects. “The focus of future work should shift away from asking whether statins generally cause these symptoms – we already have this answer,” she says. Instead, it should focus on uncovering who might actually be susceptible to certain statin-related side effects – such as people with several health problems – and why, in real-world settings, she says.