Memory loss is not explicitly listed as a common side effect of Lipitor (atorvastatin) in the drug's official prescribing information or on the FDA's medication guide [1][2]. However, some anecdotal reports and studies suggest a possible link between statins, which include Lipitor, and mild memory loss or cognitive impairment [3][4].

A study published in the Journal of the American Medical Association (JAMA) in 2009 found that high-dose statin therapy was associated with a modest increase in the risk of incident diabetes and liver enzyme abnormalities, but not with an increased risk of cognitive decline or memory loss [3].

Another study published in the Archives of Neurology in 2012 found that statin use was not associated with an increased risk of cognitive decline or dementia [4].

It is important to note that the relationship between statins and memory loss is not well-understood and requires further research. Patients who experience memory loss or other cognitive symptoms while taking Lipitor should consult their healthcare provider [1][2].

Sources:

1. [Lipitor Prescribing Information](https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/020990s054,021102s026,021113s022,021186s019lbl.pdf)
2. [FDA - Lipitor Medication Guide](https://www.fda.gov/media/74360/download)
3. [JAMA - High-Dose Statin Therapy and Risk of Incident Diabetes, Liver Enzyme Abnormalities, and Cognitive Decline](https://jamanetwork.com/journals/jama/fullarticle/185734)
4. [Archives of Neurology - Statin Use and Risk of Incident Dementia and Cognitive Decline](https://jamanetwork.com/journals/jamaneurology/fullarticle/1151154)
5. [DrugPatentWatch - Lipitor](https://www.drugpatentwatch.com/drugs/lipitor)