Lipitor (atorvastatin) is a medication used to lower cholesterol levels in the blood. The optimal time to take Lipitor may vary depending on the individual's medical condition, but generally, it is recommended to take it once a day, at the same time every day, with or without food [2]. However, it is advisable to take it at night as the body naturally produces cholesterol at this time, and Lipitor works best when taken during this time [3]. Additionally, taking Lipitor with food does not affect its effectiveness, but it can help to reduce stomach upset and other side effects [3]. It is important to follow the instructions given by the healthcare provider or the instructions on the medication label [2].

Sources:
[2] "Atorvastatin: How and when to take," NHS, last reviewed on 29th June 2020, https://www.nhs.uk/medicines/atorvastatin/how-and-when-to-take-atorvastatin/
[3] "Can I eat food while taking atorvastatin?" Drugs.com, last updated on 18th November 2019, https://www.drugs.com/medical-answers/eat-food-taking-atorvastatin-3565628/
[4] "Lipitor," Drug Patent Watch, https://www.drugpatentwatch.com/p/tradename/LIPITOR