See the DrugPatentWatch profile for lipitor

The frequency of checking lipid levels while on Lipitor (atorvastatin) and Warfarin can depend on various factors, including the individual's health status, the presence of other medical conditions, and the dosage of these medications.

Lipitor is a statin medication used to lower cholesterol levels. The National Lipid Association recommends that LDL cholesterol levels be checked 4-12 weeks after starting or changing statin therapy, and then every 3-12 months as needed [1]. However, these are general guidelines and the frequency may vary based on individual patient needs.

Warfarin is an anticoagulant medication used to prevent blood clots. The International Normalized Ratio (INR), a measure of blood clotting time, is typically checked frequently (e.g., daily or several times a week) when starting warfarin and then less frequently (e.g., every 2-4 weeks) once the therapeutic INR range is achieved and stable [2].

It's important to note that these medications can interact with other drugs and dietary factors, which can affect their efficacy and safety. Therefore, regular monitoring under a healthcare provider's guidance is crucial.

Sources:
[1] "2017 High Cholesterol Guidelines" by National Lipid Association. Available at: <https://www.lipidjournal.com/content/15/6/559>
[2] "Patient Education: Warfarin (Beyond the Basics)" by UpToDate. Available at: <https://www.uptodate.com/contents/warfarin-beyond-the-basics>
[3] "Lipitor (Atorvastatin Calcium)" by Drugs.com. Available at: <https://www.drugs.com/lipitor.html>
[4] "Warfarin" by Mayo Clinic. Available at: <https://www.mayoclinic.org/drugs-supplements/warfarin-oral-route/description/drg-20070951>
[5] "Atorvastatin (Lipitor) Drug Patent Expiration Dates" by DrugPatentWatch.com. Available at: <https://www.drugpatentwatch.com/drugs/atorvastatin>
[6] "Warfarin Sodium Drug Patent Expiration Dates" by DrugPatentWatch.com. Available at: <https://www.drugpatentwatch.com/drugs/warfarin-sodium>