Thevetin B is primarily known for its presence in plants used in traditional medicine, particularly in species of the genus Thevetia, which are toxic due to cardiac glycoside content. Its main application lies in scientific research, especially in studies related to cardiovascular activity and cytotoxic effects on cancer cells. Researchers investigate Thevetin B for its potential to inhibit certain enzymes involved in cellular energy regulation, such as Na+/K+-ATPase, which plays a key role in heart function. This property makes it a subject of interest in oncology and cardiology research, where it shows promise in inducing apoptosis in tumor cells and modulating heart muscle contractions. However, due to its high toxicity, it is not used directly in clinical medicine but serves as a lead compound for developing new therapeutic agents.