Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels and prevent heart disease [1]. According to a study published in the Journal of Pharmacy and Pharmacology, statins like Lipitor can affect muscle growth by inhibiting the production of certain proteins that are necessary for muscle growth [2]. This can lead to muscle weakness and even atrophy in some cases. However, another study conducted by researchers at the Max Delbrück Center for Molecular Medicine in Berlin found that statins can also have a positive effect on muscle growth by increasing the activity of certain proteins that promote muscle growth and repair [3].

Therefore, it is unclear whether Lipitor specifically affects muscle growth negatively or positively. While some studies suggest that statins can inhibit muscle growth, others suggest that they can have a positive effect. It is important to note that any potential negative effects of Lipitor on muscle growth are outweighed by its potential benefits in reducing the risk of heart disease. It is recommended to consult with a healthcare provider if you have concerns about the effects of Lipitor on muscle growth.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3463373/
[3] https://www.mdc-berlin.de/news/press/what-statins-do-muscles