Bile duct obstruction is a condition where the flow of bile from the liver to the small intestine is blocked. The use of certain medications, such as Lipitor, has been associated with an increased risk of bile duct obstruction. To determine if switching to a different medication can prevent bile duct obstruction with Lipitor, let's examine the provided sources.

The first source, Drug Patent Watch, provides information about Lipitor. However, it does not specifically mention bile duct obstruction as a side effect or provide any guidance on switching medications to prevent this condition [1].

The second source, a book chapter from the National Center for Biotechnology Information, discusses the pathophysiology and treatment of bile duct obstruction. It does not mention Lipitor or switching medications as a preventive measure for bile duct obstruction [2].

The third source, the National Cancer Institute's Cancer Terms Dictionary, provides definitions of medical terms related to cancer. While it does not directly address the question of switching medications to prevent bile duct obstruction, it is not directly relevant to the topic at hand [3].

Based on the provided sources, there is no explicit information or guidance regarding whether switching to a different medication can prevent bile duct obstruction with Lipitor. It is important to note that any decision regarding medication should be made in consultation with a healthcare professional who can evaluate the individual's specific medical condition and provide personalized advice.

Sources:
[1] Drug Patent Watch. Lipitor. Retrieved from: https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] National Center for Biotechnology Information. Bile Duct Obstruction - StatPearls. Retrieved from: https://www.ncbi.nlm.nih.gov/books/NBK548236/
[3] National Cancer Institute. Cancer Terms Dictionary. Retrieved from: https://www.cancer.gov/publications/dictionaries/cancer-terms/