Lipitor, a medication that contains atorvastatin, is a type of drug known as a statin that is used to lower cholesterol levels in the blood. According to the sources provided, Lipitor can be taken at any time of the day, with or without food [2][3]. However, there is some evidence to suggest that taking Lipitor at bedtime may be more effective than taking it in the morning. One study found that people who took Lipitor at bedtime had lower levels of LDL cholesterol, the so-called "bad" cholesterol, than those who took it in the morning [2]. The reason for this may be that the body produces more cholesterol at night, so taking Lipitor before bed can help to reduce the amount of cholesterol that is produced during this time [2].

It is important to note that Lipitor should be taken exactly as prescribed by a doctor or pharmacist, and patients should not change the timing or dosage of their medication without first consulting with their healthcare provider [3]. Additionally, Lipitor may cause side effects such as muscle pain, liver problems, and digestive issues, so patients should be aware of these potential risks and report any symptoms to their doctor immediately [3].

In summary, Lipitor can be taken at any time of the day, but there is some evidence to suggest that taking it at bedtime may be more effective in lowering cholesterol levels. Patients should always follow their doctor's instructions for taking Lipitor and be aware of the potential side effects associated with this medication.

Sources:
[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/