Atorvastatin

When prescribing or taking atorvastatin, it's important to consider not just its cholesterol-lowering properties, but also its broader impact on cardiovascular health and the timing of its use. Like other statins, atorvastatin has effects that extend well beyond lowering lipids—many of which play a key role in reducing overall cardiovascular risk (2, 3, 4, 7).

Statins Do Much More Than Just Lower Cholesterol

A growing body of evidence shows that statins reduce mortality across a wide range of heart conditions—including heart failure and cardiovascular disease—and can even limit the extent of heart damage after a heart attack (3, 4). Remarkably, many of these benefits occur independently of their cholesterol-lowering effect. These additional actions are known as the pleiotropic effects of statins. Some of these added benefits include (2, 3, 4, 7):

• Stabilising cholesterol deposits (atherosclerotic plaques): Statins make these fatty deposits less likely to rupture and trigger clots, partly by reducing inflammation, oxidative stress (from free radicals), and immune system overactivity.

• Improving blood vessel function: Statins help blood vessels dilate more effectively and reduce blood viscosity, which supports smoother, more efficient circulation.

• Stronger anti-inflammatory effects in certain statins: Atorvastatin, a lipophilic statin, tends to show stronger anti-inflammatory and lipid-lowering effects compared to hydrophilic statins like rosuvastatin and pravastatin.

The Body Synthesises Cholesterol in the Evening

Cholesterol production in the liver follows a natural daily rhythm. It typically peaks between 8 p.m. and midnight—up to four times higher than in the morning hours (12). Because of this, taking statins at night—especially shorter-acting ones—can help maximise their effectiveness in reducing cholesterol levels.

Atorvastatin Side Effects

Atorvastatin is generally well tolerated and widely prescribed. However, like all medications, it can cause side effects in some people. Knowing what to expect—especially the common and less common effects—can help you stay informed and seek advice if needed.

Muscle-Related Side Effects

Atorvastatin is a lipophilic statin, meaning it easily penetrates body tissues, including muscles and the brain. This property enhances its ability to lower cholesterol and reduce inflammation—but it also increases the likelihood of certain side effects (3).

Muscle-related symptoms are the most commonly reported side effects of statin therapy, experienced by a significant number of patients. However, compared to simvastatin, atorvastatin has been shown to cause fewer statin-associated muscle symptoms (SAMS) (5, 6, 7).

Observe the Condition of Your Muscles

If you experience muscle pain, soreness, or tenderness that isn’t clearly linked to physical activity or a recent viral infection, speak with your pharmacist or GP. These could be early signs of statin-related muscle symptoms.

Muscle-related side effects occur in an estimated 10–29% of patients (6) and are in fact the leading reason why people stop taking statins.

The most commonly affected areas include the thighs, calves, and hip flexors, and symptoms are usually symmetrical (6).

Who Is at Greatest Risk of Muscle Side Effects?

Certain factors can increase the risk of developing statin-associated muscle symptoms. These include (11):

• Age over 60

• Diabetes

• Hypothyroidism

• Multisystem diseases

• Vitamin D deficiency

• Excessive or strenuous physical activity

• Alcohol consumption

• Major surgery

• Higher statin doses — this is the strongest risk factor, increasing the risk sixfold compared to lower doses
  
  

Memory and Mood

There are also increasing reports of memory issues associated with statins—particularly at higher doses. Although clinical evidence remains mixed, if you’ve recently started or increased your dose and notice memory lapses, difficulty focusing, or low mood, consult your pharmacist or GP (8, 9).

Myasthenia Gravis – A New Warning with Statin Use

If you have myasthenia gravis and notice a worsening of symptoms while taking statins, speak with your GP. Although rare, statins have been reported to aggravate this condition, so any changes should be reviewed promptly (5).

Other Possible Side Effects

In addition to muscle-related symptoms, atorvastatin may cause a range of other side effects (5). These are generally less common but still important to be aware of—especially if they persist or begin to affect your quality of life:

• Painful joints

• General lack of energy or strength

• Dizziness

• Sleep disturbances

• Liver disorders

• Memory problems

Understanding your individual risk of side effects—especially from statins—can be challenging. A pharmacogenomics (PGx) test in the UK can help identify how your genes influence your response to medications like atorvastatin, supporting safer, more personalised medicine through genetic testing for medication response.

Genetic variation can affect both how well atorvastatin works and your risk of side effects. One of the most important genes involved is SLCO1B1, which encodes the OATP1B1 transporter. This protein helps move statins like atorvastatin into the liver, where they carry out their cholesterol-lowering effects (10, 11).

Key points about SLCO1B1 and statin response:

• SLCO1B1 is essential for the liver uptake of statins.

• Reduced transporter function can lead to higher levels of statins in the bloodstream and a greater risk of muscle-related side effects.

• The c.521T>C variant (rs4149056) is strongly linked with statin-induced myopathy.

• People with two copies of the C allele (C/C genotype) are at significantly higher risk of muscle damage—especially from simvastatin and lovastatin.

Related Medications:

Pharmacogenetic factors may also be important for other statins, particularly:

• Simvastatin

• Rosuvastatin

• Pravastatin