Based on the information provided, there is no direct link between Lipitor and Tums that would suggest muscle discomfort as a combined effect.

Lipitor, a medication used to treat high cholesterol, is a statin that works by reducing the amount of cholesterol your body makes [1]. Common side effects of Lipitor include diarrhea, upset stomach, muscle pain, and joint pain [1].

On the other hand, Tums is an antacid used to treat heartburn, sour stomach, acid indigestion, and upset stomach [2]. It works by neutralizing stomach acid. There are no known interactions between Lipitor and Tums that would result in muscle discomfort [3].

However, it is important to note that everyone's body reacts differently to medications and supplements. If you have noticed muscle discomfort since combining Lipitor and Tums, it would be best to consult with your healthcare provider to determine if there is a potential interaction or if there is another underlying cause for your discomfort.

Sources:
[1] <https://www.drugpatentwatch.com/p/tradename/LIPITOR>
[2] <https://www.mayoclinic.org/drugs-supplements/azithromycin-oral-route/precautions/drg-20072362?p=1>
[3] <https://labeling.pfizer.com/ShowLabeling.aspx?id=16892&Section=PPI>