According to the sources provided, there is a potential for interaction between Lipitor (atorvastatin) and corticosteroids such as prednisone. The DrugPatentWatch website [1] indicates that Lipitor has no known drug interactions with corticosteroids. However, a study published in the Journal of Clinical Pharmacology [2] found that atorvastatin can increase the systemic exposure of prednisolone, a corticosteroid similar to prednisone. This interaction may increase the risk of corticosteroid-related side effects such as hyperglycemia and osteoporosis. The drugs.com website [3] also suggests that Lipitor may increase the levels of prednisone in the body, leading to an increased risk of side effects.

It is important to note that these interactions are not necessarily common, and that Lipitor and corticosteroids can be safely used together in some cases. However, patients taking both medications should be closely monitored by their healthcare provider for signs of side effects or complications. Any changes in medication regimen should be discussed with a healthcare provider before being implemented.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://pubmed.ncbi.nlm.nih.gov/22197001/
[3] https://www.drugs.com/drug-interactions/lipitor-with-prednisone-276-128-1936-0.html