Based on the information available, there is no definitive evidence to suggest that generic Lipitor (atorvastatin) has different side effects compared to brand-name Lipitor. The U.S. Food and Drug Administration (FDA) requires that generic drugs have the same active ingredients, strength, dosage form, and route of administration as their brand-name counterparts. They must also have the same therapeutic effect.

However, there can be minor differences in inactive ingredients, such as binders, fillers, and dyes, which can cause slight variations in the size, shape, or color of the generic drug compared to the brand-name drug. These differences should not affect the drug's safety or efficacy [1].

It is important to note that, like all medications, both brand-name and generic Lipitor can cause side effects. Common side effects of atorvastatin include diarrhea, upset stomach, and muscle pain [2].

According to DrugPatentWatch.com, the patent for Lipitor expired in 2011, allowing generic versions of the drug to enter the market [3]. Since then, multiple generic manufacturers have produced atorvastatin, which has helped increase access to this important cholesterol-lowering medication.

In summary, based on the available information, there is no evidence to suggest that generic Lipitor has different side effects compared to brand-name Lipitor. Both brand-name and generic atorvastatin can cause side effects, but these should be similar for both versions of the drug.

Sources:
[1] U.S. Food and Drug Administration. (2013). Generic Drugs: Questions and Answers. Retrieved from <https://www.fda.gov/drugs/understanding-generic-drugs/generic-drugs-questions-and-answers>
[2] Mayo Clinic. (2021). Atorvastatin (Oral Route). Retrieved from <https://www.mayoclinic.org/drugs-supplements/atorvastatin-oral-route/side-effects/drg-20067100>
[3] DrugPatentWatch.com. (n.d.). Lipitor (Atorvastatin Calcium) Drug Patent Expiration. Retrieved from <https://www.drugpatentwatch.com/drugs/lipitor>