Lipitor is a medication used to lower cholesterol levels in the blood, and it is usually prescribed for long-term use. According to Drug Patent Watch [1], the patent for Lipitor expired in 2011, and now there are several generic versions available. The recommended duration of Lipitor treatment depends on the individual's condition and response to the medication. As per the National Health Service (NHS) [3], doctors usually prescribe a daily dose of 10-80 mg, and the treatment duration can vary from a few months to several years. The medication's effectiveness is not influenced by the time of day it is taken, as stated by Drugs.com [2]. However, it is essential to take the medication at the same time every day to ensure consistent blood levels of the drug. It is crucial to follow the doctor's instructions on the duration of treatment and not stop taking Lipitor without consulting a healthcare professional. Long-term use of Lipitor can help reduce the risk of heart disease, stroke, and other cardiovascular conditions. It is also important to maintain a healthy lifestyle, including a balanced diet and regular exercise, to complement the medication's effects.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.drugs.com/medical-answers/does-lipitor-work-better-if-you-take-it-at-night-416127/
[3] https://www.nhs.uk/medicines/atorvastatin/how-and-when-to-take-atorvastatin/