The shelf life of bulk Lipitor, also known as atorvastatin, can vary depending on several factors. According to the information provided by the sources, we can gather some insights.
The first source, DrugPatentWatch, does not directly provide information about the shelf life of Lipitor. Instead, it focuses on patent expiration dates for various drugs, including Lipitor. While this source does not give us specific information about the shelf life, it does indicate that Lipitor has been on the market since 1996 and its patent expired in 2011 [1]. This suggests that Lipitor has been available for a considerable amount of time and has likely undergone stability testing to determine its shelf life.
The second source, a book published on the National Center for Biotechnology Information (NCBI) website, provides a general understanding of drug stability and expiration dates. It states that drug manufacturers are required to conduct stability studies to determine the expiration date of a drug. These studies involve evaluating the drug's chemical and physical stability over time under various storage conditions. The expiration date is typically set based on the longest period of time that the drug remains stable and maintains its potency [2].
The third source, PubChem, provides detailed information about atorvastatin, the active ingredient in Lipitor. While it does not directly mention the shelf life of Lipitor, it does state that atorvastatin is stable under normal conditions and is not affected by temperature changes [3]. This suggests that Lipitor, which contains atorvastatin, may have a relatively long shelf life if stored properly.
Considering the information from these sources, it can be inferred that Lipitor likely has a shelf life determined through stability studies conducted by the manufacturer. However, without specific data from the manufacturer or additional sources, it is challenging to provide an exact shelf life for bulk Lipitor.
In conclusion, while we do not have specific information about the shelf life of bulk Lipitor from the provided sources, it can be assumed that Lipitor has undergone stability testing to determine its expiration date. The general understanding is that the expiration date is based on the drug's stability and potency over time. It is important to note that proper storage conditions, such as temperature control and protection from light and moisture, can also play a significant role in maintaining the drug's shelf life.
Sources:
[1] DrugPatentWatch: https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] National Center for Biotechnology Information (NCBI): https://www.ncbi.nlm.nih.gov/books/NBK430779/
[3] PubChem: https://pubchem.ncbi.nlm.nih.gov/compound/Atorvastatin