Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the blood. According to the Mayo Clinic [2], some of the most common side effects of Lipitor include headache, muscle aches and pains, diarrhea, and constipation. Other possible side effects include liver damage, memory loss, and an increased risk of developing type 2 diabetes. However, these side effects are rare and usually occur in people who take high doses of the drug or who have pre-existing medical conditions.

Medical News Today [3] adds that Lipitor may also interact with other medications, including antibiotics, antifungal drugs, and blood thinners. Patients should always inform their doctor of any medications they are taking before starting Lipitor.

Drug Patent Watch [1] provides information on the expiration of Lipitor's patent, which means that generic versions of the drug are now available. While these generic versions contain the same active ingredient as Lipitor, they may have different inactive ingredients that could cause different side effects. Patients who experience side effects while taking Lipitor or its generic versions should talk to their doctor about alternative medications.

In conclusion, Lipitor may cause some side effects, but they are generally mild and rare. Patients should always inform their doctor of any medications they are taking and report any unusual symptoms. If side effects occur, patients should talk to their doctor about alternative medications.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013
[3] https://www.medicalnewstoday.com/articles/drugs-lipitor-side-effects