Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the body. Joint pain is a known side effect of atorvastatin, and it is important to speak with a healthcare provider about any concerns regarding medication use.

According to the sources provided, there is no specific recommendation for how often to take Lipitor for joint pain. The frequency of medication use is typically determined by the healthcare provider based on the individual's medical history, current health status, and other factors.

It is important to note that joint pain is a relatively rare side effect of atorvastatin, affecting less than 1% of patients taking the medication [3]. If joint pain is experienced while taking Lipitor, it is important to discuss this with a healthcare provider to determine the best course of action.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.goodrx.com/atorvastatin/what-is
[3] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013