Based on the available information, there is no specific interaction between Acetaminophen (Tylenol) and Lipitor (Atorvastatin) that would require a modification in the dosage of Acetaminophen.

Acetaminophen is a common over-the-counter medication used to treat pain and reduce fever. Lipitor, on the other hand, is a prescription drug used to treat high cholesterol levels.

However, it is essential to consult with a healthcare provider or pharmacist before combining any medications, including over-the-counter drugs, to ensure safety and effectiveness. It is also important to follow the recommended dosage on the label of the medication and not exceed the maximum daily dosage of Acetaminophen, which is typically 3,000 milligrams per day for adults [1].

In addition, it is worth noting that Lipitor can increase the levels of liver enzymes in the blood, which can be a sign of liver damage. Therefore, it is crucial to monitor liver function regularly when taking Lipitor [2]. Acetaminophen is metabolized in the liver, and high doses can cause liver damage. Therefore, it is essential to be cautious when taking both medications [3].

In summary, while there is no specific interaction between Acetaminophen and Lipitor that requires a modification in the dosage of Acetaminophen, it is crucial to consult with a healthcare provider or pharmacist before combining any medications and to follow the recommended dosage on the label of the medication.

Sources:

1. Mayo Clinic. (2021). Acetaminophen (Oral Route). Retrieved from <https://www.mayoclinic.org/drugs-supplements/acetaminophen-oral-route/side-effects/drg-20068783>
2. Drugs.com. (2021). Lipitor. Retrieved from <https://www.drugs.com/lipitor.html>
3. DrugPatentWatch. (2021). Acetaminophen and Atorvastatin. Retrieved from <https://www.drugpatentwatch.com/drugs/acetaminophen-and-atorvastatin/>