Based on the provided sources, there are no specific limitations mentioned regarding the amount of Lipitor that can be purchased with the discount. However, it is important to note that the availability and extent of discounts may vary depending on factors such as insurance coverage, pharmacy policies, and individual eligibility.

The first source, Drug Patent Watch, provides information about the drug Lipitor but does not mention any specific limitations on the purchase amount with the discount [1].

The second source, the official Lipitor website, offers a savings program called "Lipitor For You." It states that eligible patients may pay as little as $10 per month for their Lipitor prescription. However, the website does not specify any limitations on the purchase amount [2].

The third source, GoodRx, provides information on the Medicare coverage of atorvastatin, the generic version of Lipitor. It mentions that Medicare Part D plans may cover atorvastatin, but the specific coverage details may vary. The source does not provide any information on limitations regarding the purchase amount [3].

While the sources do not explicitly mention any limitations on the purchase amount of Lipitor with the discount, it is always recommended to check with your insurance provider, pharmacy, or healthcare professional for specific details regarding coverage, discounts, and any potential limitations that may apply.

Sources:
[1] Drug Patent Watch - Lipitor: https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] Lipitor Official Website - Savings: https://www.lipitor.com/en/savings
[3] GoodRx - Atorvastatin Medicare Coverage: https://www.goodrx.com/atorvastatin/medicare-coverage