Lipitor is a medication used to lower cholesterol levels in the blood and reduce the risk of heart disease. According to DrugPatentWatch [1], the dosage of Lipitor has not changed since its initial approval in 1996. The recommended starting dose is typically 10-20mg per day, with the maximum dose being 80mg per day. However, the dosage may be adjusted based on individual patient needs and response to treatment.

A study published in the National Center for Biotechnology Information [2] found that a lower dose of Lipitor (10mg) was just as effective as a higher dose (80mg) in reducing LDL cholesterol levels in patients with stable coronary artery disease. The study suggests that lower doses of Lipitor may be just as effective in certain patient populations, which could potentially reduce the risk of side effects associated with higher doses.

Despite the availability of generic versions of Lipitor, Pfizer's sales of the drug have remained strong. According to Axios [3], Lipitor generated over $1 billion in sales for Pfizer in 2019. The article notes that Pfizer has been successful in maintaining Lipitor's market share through various strategies, including targeted marketing to specific patient populations and offering rebates to insurance companies.

In conclusion, the recommended dosage of Lipitor has remained the same since its initial approval in 1996. However, lower doses of the medication may be just as effective in certain patient populations. Despite the availability of generic versions, Lipitor continues to be a profitable drug for Pfizer due to their successful marketing strategies and rebate offerings to insurance companies.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6044319/
[3] https://www.axios.com/2019/10/30/lipitor-pfizer-drug-patent-sales-2019