While the Cardiolite stress test and the Lexiscan stress test are both nuclear stress tests, they stress the heart in different ways. The Cardiolite test can be performed either with exercise or with drugs, while the Lexiscan test requires a drug called
regadenoson that causes the effects of exercise on the heart. Sometimes a Lexiscan thallium stress test is selected, in which case a different radiotracer (thallium) is used to generate the images.