Lipitor (atorvastatin) is a medication used to lower cholesterol levels in the blood. It belongs to a class of drugs called statins, which work by inhibiting the production of cholesterol in the liver. According to the sources provided, there are no known interactions between Lipitor and low-fat substitutes.

The first source [1] provides information on the patent status of Lipitor and its generic equivalents. It does not provide any information on the interactions between Lipitor and low-fat substitutes.

The second source [2] is from WebMD, a reputable health website. It provides information on the uses, side effects, and precautions of Lipitor. It also includes a section on drug interactions, but it does not mention any interactions between Lipitor and low-fat substitutes.

The third source [3] is a research article published in the Journal of Lipid Research. It discusses the effects of statins on lipid metabolism and the potential benefits of combining statins with dietary interventions. However, it does not provide any specific information on the interactions between Lipitor and low-fat substitutes.

In conclusion, based on the sources provided, there are no known interactions between Lipitor and low-fat substitutes. However, it is always important to consult with a healthcare provider before making any changes to your medication or diet.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.webmd.com/drugs/2/drug-3330/lipitor-oral/details
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4593660/