Based on the information available, there is no definitive answer to how long it takes for Lipitor to affect flexibility. Lipitor, also known as atorvastatin, is a medication used to treat high cholesterol levels [1]. It works by reducing the amount of cholesterol produced by the liver [1].

Flexibility, in this context, could be referring to the flexibility of blood vessels or muscles. Lipitor's mechanism of action does not directly affect the flexibility of blood vessels or muscles. However, by reducing cholesterol levels, it may help prevent or slow the progression of atherosclerosis, a condition characterized by the hardening and narrowing of the arteries [1]. This could potentially lead to improvements in blood flow and, consequently, the flexibility of blood vessels over time.

It is important to note that Lipitor's effects on cholesterol levels are usually observed after several weeks to months of regular use [1]. Therefore, any potential effects on flexibility would likely not be immediate and would require consistent use of the medication.

In conclusion, while Lipitor does not have an immediate effect on flexibility, its long-term use may contribute to improvements in blood vessel flexibility by reducing cholesterol levels. As with any medication, it is crucial to consult with a healthcare provider before starting or changing any medication regimen.

Sources:
[1] DrugPatentWatch.com - Lipitor (atorvastatin) - <https://www.drugpatentwatch.com/drugs/lipitor>