Lipitor is a medication used to lower cholesterol levels in the blood. According to the Mayo Clinic [2], some common side effects of Lipitor include diarrhea, joint pain, and muscle pain. However, stomach discomfort is not listed as a common side effect.

Drugwatch [3] also provides a list of potential side effects of Lipitor, including muscle pain, liver damage, and an increased risk of diabetes. Again, stomach discomfort is not mentioned as a common side effect.

Drug Patent Watch [1] provides information about the drug Lipitor, including its active ingredient, atorvastatin. However, it does not provide any information about potential side effects.

In conclusion, stomach discomfort is not listed as a common side effect of Lipitor according to the sources provided. However, it is important to note that every individual may react differently to medications, and some people may experience stomach discomfort while taking Lipitor. If you are experiencing any side effects while taking Lipitor, it is important to speak with your healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.mayoclinic.org/drugs-supplements/atorvastatin-oral-route/side-effects/drg-20067003
[3] https://www.drugwatch.com/lipitor/side-effects/