Lipitor (atorvastatin) and Zocor (simvastatin) are both medications used to lower cholesterol levels in the blood. They belong to a class of drugs called statins, which work by blocking the enzyme responsible for producing cholesterol in the liver.

According to Drug Patent Watch [1], Lipitor was first approved by the FDA in 1996, while Zocor was approved in 1991. Lipitor is produced by Pfizer, while Zocor is produced by Merck. Both drugs are available in tablet form and are taken orally.

A comparison of the two drugs on MedicineNet [2] shows that Lipitor is generally more effective at lowering LDL (bad) cholesterol levels than Zocor. Lipitor can lower LDL cholesterol by up to 60%, while Zocor can lower it by up to 50%. Lipitor is also more effective at raising HDL (good) cholesterol levels than Zocor.

GoodRx [3] notes that both drugs have similar side effects, including muscle pain, liver damage, and an increased risk of developing diabetes. However, Lipitor is less likely to cause muscle pain and weakness than Zocor.

In terms of cost, GoodRx [3] reports that generic versions of both drugs are available and are similarly priced. However, Lipitor is generally more expensive than Zocor when purchased as a brand-name drug.

In conclusion, while both Lipitor and Zocor are effective at lowering cholesterol levels, Lipitor appears to be more effective at reducing LDL cholesterol and raising HDL cholesterol. Lipitor is also less likely to cause muscle pain and weakness than Zocor. However, both drugs have similar side effects and are similarly priced as generics. It is important to consult with a healthcare provider to determine which medication is best for an individual's specific needs and medical history.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.medicinenet.com/atorvastatin_lipitor_vs_simvastatin_zocor/drug-vs.htm
[3] https://www.goodrx.com/conditions/high-cholesterol/atorvastatin-vs-simvastatin-which-is-better-for-high-cholesterol