Generic atorvastatin (the active ingredient in Lipitor) has the same potency as original Lipitor. Both deliver equivalent therapeutic effects because generics must demonstrate bioequivalence to the brand-name drug under FDA standards, meaning they release the same amount of active ingredient into the bloodstream within the same timeframe (typically 80-125% of the brand's AUC and Cmax).

Clinical studies and FDA approvals confirm no meaningful differences in efficacy or potency for treating high cholesterol or cardiovascular risk. For instance, generic versions approved since 2011 match Lipitor's 10 mg, 20 mg, 40 mg, and 80 mg strengths exactly.[1][2]

Minor differences may exist in inactive ingredients (e.g., fillers, dyes), which can affect appearance, taste, or rare tolerability but not potency or blood levels.[3]

Sources
[1] FDA: Generic Drug Facts
[2] DrugPatentWatch.com: Lipitor Generic Entry and Equivalence
[3] FDA: Q&A on Generic Drugs