A BMJ study found some statins can increase the risk of liver dysfunction, acute renal failure, myopathy and cataract.
Lead author Professor Julia Hippisley-Cox from the University of Nottingham said the benefits of statins to reduce heart disease continued to outweigh the risks. But, she added, GPs should be aware that a small number of people may be at risk of unintended effects.
'The important thing is to balance up the risks and benefits of medication for an individual patient so that the patient can make an informed choice.'
The researchers studied two million patients, including 225,922 new users of statins, to assess the drugs' effects in a representative population.
They found no association bet-ween use of individual statins and risk of Parkinson's disease, rheumatoid arthritis, venous thromboembolism, dementia, osteoporotic fracture, or many cancers including gastric, colon, lung, renal, breast or prostate.
But researchers estimated that for every 10,000 women treated with statins there would be 65 extra cases of liver dys-function and 252 extra cataract cases. Among men, there are likely to be 22 additional cases of acute renal failure and 95 cases of myopathy.
RCGP chairman Professor Steve Field said the paper highlighted the need for GPs to remember the side-effect profile of statins, and to treat every patient as an individual when a drug comes up in a review.
'GPs should read the paper and bear it in mind when treating patients,' he said.