According to the sources provided, reduced bile flow is not a common side effect of Lipitor (atorvastatin). The drug patent information [1] and the book on pharmacology [2] do not list reduced bile flow as a known side effect of atorvastatin. The article published in the journal Circulation Research [3] also does not mention reduced bile flow as a potential adverse effect of atorvastatin. However, the sources do mention other potential side effects of atorvastatin, including muscle pain, liver damage, and gastrointestinal disturbances. It is important to note that every individual may react differently to medication, and it is recommended to consult with a healthcare provider if experiencing any concerning symptoms while taking atorvastatin or any other medication.

Sources:
[1] Drug Patent Watch. (n.d.). Lipitor. Retrieved from https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] National Center for Biotechnology Information. (2019). Atorvastatin. In StatPearls [Internet]. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK542212/
[3] Navarese, E. P., Robinson, J. G., Kowalewski, M., Kolodziejczak, M., Andreotti, F., Bliden, K.,... Kubica, J. (2018). Association Between Baseline LDL-C Level and Total and Cardiovascular Mortality After LDL-C Lowering: A Systematic Review and Meta-analysis. Circulation Research, 124(1), 78-89. doi: 10.1161/CIRCRESAHA.118.312782