Lipitor is a medication that is used to lower cholesterol levels in the body. It is a statin drug that works by blocking an enzyme that the body uses to produce cholesterol. The effectiveness of Lipitor is not affected by the time of day it is taken. According to the National Health Service (NHS) [3], Lipitor can be taken at any time of the day, with or without food. However, taking Lipitor at night may be more convenient for some people as it can be taken with the evening meal.

The website Drugs.com [2] also states that there is no significant difference in the effectiveness of Lipitor when taken at night or during the day. However, taking Lipitor at night may be more beneficial for people who have a higher risk of heart disease, as this is when the body produces more cholesterol.

The Drug Patent Watch website [1] provides information on the patent status of Lipitor and does not provide any information on the effectiveness of the medication at different times of the day.

In conclusion, while taking Lipitor at night may be more convenient for some people, there is no evidence to suggest that it is more effective than taking it during the day. It is important to follow the instructions provided by your doctor or pharmacist and take Lipitor as directed.

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/