Generic versions of Lipitor, known as atorvastatin, are considered as effective as the brand-name drug. Atorvastatin has been shown to be bioequivalent to Lipitor, meaning it is absorbed in the body in a similar way and produces the same effects. Studies have demonstrated that switching from brand-name Lipitor to generic atorvastatin does not lead to any decrease in effectiveness or increase in side effects. This has been supported by research published in the National Center for Biotechnology Information [3]. Patients can typically expect the same benefits from generic atorvastatin as they would from the brand-name drug, with the added advantage of potential cost savings [2]. It is important for patients to consult with their healthcare provider to ensure that switching to a generic version is appropriate for their individual health needs.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.health.harvard.edu/blog/switching-to-generic-lipitor-201202064195
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5514478/