Yes, generic Lipitor is available. According to [1], the patent for Lipitor expired in 2011, which allowed for generic versions of the drug to be produced and sold. As a result, several companies, including Ranbaxy, Watson Pharmaceuticals, and Mylan, have been authorized to produce and sell generic versions of Lipitor. These generic versions are known as atorvastatin, which is the active ingredient in Lipitor.

[2] confirms that generic atorvastatin is available in the United States. The website states that there are multiple manufacturers of atorvastatin, and the drug is available in various strengths and forms, including tablets and oral solutions. The availability of generic atorvastatin has led to a decrease in the cost of the drug, making it more affordable for patients.

According to [3], the availability of generic Lipitor has had a significant impact on the pharmaceutical industry. Lipitor was one of the best-selling drugs in history, and its patent expiration led to a loss of revenue for Pfizer, the company that developed and marketed the drug. However, the availability of generic atorvastatin has also provided opportunities for other companies to enter the market and offer more affordable options for patients.

In conclusion, generic Lipitor, also known as atorvastatin, is available in the United States. The expiration of Lipitor's patent in 2011 allowed for other companies to produce and sell generic versions of the drug, which has led to a decrease in the cost of the drug and provided more affordable options for patients.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.drugs.com/availability/generic-lipitor.html
[3] https://www.latimes.com/health/la-xpm-2012-jan-16-la-he-lipitor-generic-20120116-story.html