Lipitor is a commonly prescribed medication for the treatment of high cholesterol. Atorvastatin, the active ingredient in Lipitor, is a type of medication called a statin that works by blocking the production of cholesterol in the liver. According to [2], there are no known side effects of taking Lipitor specifically before bed. However, it is generally recommended to take Lipitor at night because the body produces more cholesterol during the night than during the day, and taking Lipitor at night can help to lower cholesterol levels more effectively [3]. Additionally, taking Lipitor at night can help to reduce the risk of muscle pain and weakness, which are potential side effects of statin medications [3]. It is important to note that while Lipitor is generally considered safe and effective, it may cause side effects in some people. Common side effects of Lipitor include muscle pain, diarrhea, and nausea, and rare but serious side effects include liver problems and muscle damage [1]. It is important to talk to a healthcare provider before starting Lipitor or any other medication, and to report any side effects that may occur.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.bhf.org.uk/informationsupport/heart-matters-magazine/medical/ask-the-experts/statins-and-sleep
[3] https://www.khealth.com/learn/high-cholesterol/when-to-take-atorvastatin-morning-or-night/