Lipitor is a medication used to lower cholesterol levels in the blood [1]. According to the sources provided, insomnia is not listed as a common side effect of Lipitor. However, medications can affect individuals differently, and some people may experience insomnia while taking Lipitor [2]. Insomnia is a sleep disorder that can be caused by various factors, including medications [3]. According to AARP, some medications, such as beta-blockers, antidepressants, and steroids, can cause insomnia [2]. GoodRx also notes that certain medications, including some cholesterol-lowering drugs, can cause sleep disturbances [3]. It is important to talk to a healthcare provider if insomnia occurs while taking Lipitor or any other medication.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.aarp.org/health/drugs-supplements/info-04-2013/medications-that-can-cause-insomnia.html
[3] https://www.goodrx.com/conditions/insomnia/could-your-medication-be-causing-insomnia