Lipitor is a brand name for the drug atorvastatin, which is a medication used to lower cholesterol levels in the body [1]. According to the Mayo Clinic, ginkgo supplements are commonly used to improve memory and cognitive function [2]. However, there is no evidence to suggest that Lipitor reduces the effectiveness of ginkgo supplements.

That being said, it is important to note that certain supplements and foods can interact with medications, including Lipitor. For example, grapefruit and grapefruit juice can increase the level of Lipitor in the blood, which can lead to an increased risk of side effects [3]. Additionally, supplements such as St. John's wort and red yeast rice can also interact with Lipitor and potentially increase the risk of side effects.

Therefore, it is important to talk to a healthcare provider before taking any supplements while on Lipitor. They can provide guidance on which supplements may be safe to take and which ones to avoid to prevent any potential interactions.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.mayoclinic.org/drugs-supplements-ginkgo/art-20362032
[3] https://www.heart.org/en/health-topics/consumer-healthcare/medication-information/medication-interactions-food-supplements-and-other-drugs