There is no evidence to suggest that drinking orange juice decreases the effectiveness of Lipitor, a medication used to lower cholesterol levels. According to the drug patent information [1], Lipitor's active ingredient is atorvastatin calcium, which works by inhibiting the production of cholesterol in the liver. Orange juice does not interfere with this mechanism of action.

However, it is important to note that grapefruit juice, not orange juice, has been found to interact with Lipitor and other statins [2]. Grapefruit juice contains compounds that inhibit the activity of an enzyme responsible for breaking down statins in the body. This can lead to higher levels of the medication in the bloodstream, increasing the risk of side effects.

While orange juice does not have the same effect as grapefruit juice on statin medications, it is still important to be aware of potential food-drug interactions. The AARP [2] recommends that individuals taking Lipitor should avoid consuming large amounts of alcohol and limit their intake of high-fat foods, as these can interfere with the medication's effectiveness.

In conclusion, there is no evidence to suggest that drinking orange juice decreases the effectiveness of Lipitor. However, individuals taking Lipitor should be aware of potential food-drug interactions and should consult with their healthcare provider or pharmacist before making any significant changes to their diet or medication regimen.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.aarp.org/health/drugs-supplements/info-2022/food-medication-interaction.html
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3750609/