Expert advice on the key warning sign to watch for with England’s most prescribed medication
Statins are commonly taken(Image: Anastasiia Krivenok via Getty Images)
With atorvastatin being the most commonly prescribed drug in England last year, a pharmacist has revealed one crucial side effect that patients must not disregard, while also debunking misconceptions about whether the medicine can genuinely reduce cholesterol levels. According to the British Heart Foundation, approximately eight million people across the UK are now taking statins each year, with numbers continuing to rise, meaning frontline pharmacists are encountering increasing numbers of patients wanting reassurance about initial side effects and safe management strategies.
Superintendent Pharmacist Peter Thnoia, from NHS-registered pharmacy PillTime, has provided advice on the most frequent early reactions to atorvastatin, when patients ought to consult medical professionals and the timeframe in which they can anticipate seeing significant improvements in their cholesterol readings.
What is the most common side effect of atorvastatin that patients shouldn’t ignore?
Peter said: “Some side effects of atorvastatin may settle after the first few days as the body adjusts. However, muscle pain that does not ease remains the key early side effect to watch out for, especially if it worsens or begins to affect larger muscle groups.
“This discomfort can range from mild to increasingly severe, but both cases should be taken seriously and prompt patients to contact their GP surgery. The patient information leaflet that is provided alongside the atorvastatin prescription refers to this as myopathy, which essentially means muscle pain, so it’s important that patients familiarise themselves with the side effects listed in this leaflet.
“When pain becomes significant enough to limit physical activity, it may indicate that an alternative treatment to atorvastatin is needed. In some severe cases, atorvastatin can lead to damage to the muscle fibre, so it’s important that muscle pain that increases in pain, or does not go away, is flagged with your GP or prescriber. Your GP may request blood tests to establish what is happening and whether atorvastatin is a good fit or if an alternative treatment is needed.”

Watch our for muscle pain(Image: m-gucci via Getty Images)
Does atorvastatin have any beneficial effects such as changes to cholesterol?
Peter said: “Patients can expect to see a significant drop in cholesterol levels in the blood after about four weeks, which a blood test can confirm. If a blood test isn’t available from your NHS GP to confirm this, then private testing is also an option.
“Whilst patients can expect a significant drop in cholesterol levels in the blood within the first four weeks, it takes much longer for the body to reap the benefits of this. It takes time for your body to adjust to the medication and to the lower cholesterol levels in the blood. Over several months to years, lower cholesterol will mean there’s less fatty plaque building up in the arteries, so blood flows easier around the body.
“Gradually over time, and with the right healthy lifestyle adaptations, patients will feel more energised and alert. However, because the benefits are subtle and build over time, it can be really beneficial to have a blood test to check the cholesterol levels in the body, so that patients know whether or not the treatment is working and worth continuing.”

A pharmacist has issued a note of caution(Image: samael334 via Getty Images)
How does the tolerability of atorvastatin compare with other statins?
As the beginning of the new year may prompt patients to reassess their medication options, Peter has offered guidance on tolerability for those contemplating a switch to atorvastatin: “As with any medicine, tolerance is often down to individual patients and their personal circumstances, as well as how side effects are managed.
“Tolerance to atorvastatin varies from person to person, and there is no single factor that reliably predicts how someone will respond. If the first month of treatment passes without issues, it’s likely that most people can continue taking the medication without difficulty.
“The key here is to make sure that patients are familiar with the side effects listed within the patient medication leaflet and that they flag any concerns with their GP, so that side effects are monitored and managed.”
Peter Thnoia serves as Superintendent Pharmacist at NHS-registered pharmacy PillTime, and is a registered pharmacist with the General Pharmaceutical Council. He brings more than 25 years of pharmacy expertise to his role.