According to the sources provided, Lipitor (atorvastatin) is a medication used to lower cholesterol levels in the blood. It belongs to a class of drugs called statins. The sources do not explicitly state whether Lipitor should be taken at night or during the day. However, they do provide some information that can help us understand the best way to take Lipitor.

The first source, Drug Patent Watch, provides information about the drug but does not mention anything about the timing of its administration [1].

The second source, Drugs.com, suggests that there is no specific time of day that Lipitor needs to be taken. It states that Lipitor can be taken with or without food, and it is usually taken once daily [2]. The article also mentions that taking Lipitor at the same time each day can help establish a routine and make it easier to remember to take the medication.

The third source, NHS (National Health Service), provides general information about atorvastatin, the active ingredient in Lipitor. It advises taking atorvastatin once daily, preferably in the evening, as cholesterol production is highest during the night [3]. However, it also states that atorvastatin can be taken at any time of the day, as long as it is taken consistently.

In summary, while there is no specific time mentioned in the sources for taking Lipitor, it is generally recommended to take it once daily at the same time each day. Taking it in the evening may be preferred, as cholesterol production is highest during the night. However, Lipitor can be taken at any time of the day as long as it is taken consistently. It is always best to follow the instructions provided by your healthcare provider or the instructions on the medication label.

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