Lipitor, also known as atorvastatin, is a medication used to lower cholesterol levels in the body. According to Drug Patent Watch [1], Lipitor is one of the most commonly prescribed medications in the United States. However, as with any medication, there are potential side effects to be aware of.

One of the potential side effects of Lipitor is muscle weakness. According to the Mayo Clinic [2], muscle weakness is a rare but possible side effect of statins, including Lipitor. The exact prevalence of Lipitor-induced muscle weakness is difficult to determine, as it can vary depending on the individual and their medical history.

A study published in the Journal of Pharmacy and Therapeutics [3] found that muscle weakness was reported in 1.5% of patients taking Lipitor. However, the study notes that this is likely an underestimate, as many patients may not report mild muscle symptoms.

It is important to note that muscle weakness can be a sign of a more serious condition known as rhabdomyolysis, which is a breakdown of muscle tissue that can lead to kidney damage. While rare, rhabdomyolysis can be a serious side effect of statins, including Lipitor. It is important to seek medical attention immediately if you experience severe muscle weakness or pain while taking Lipitor.

In conclusion, while Lipitor-induced muscle weakness is a potential side effect of the medication, it is rare and affects a small percentage of patients. It is important to be aware of the potential side effects of any medication and to discuss any concerns with your healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2949584/