Developing new drugs against cancer and obtaining approvals for novel drugs are often expensive and resource-intensive processes. Repurposing drugs for oncologic use has gained increasing attention as a cost-effective and time-efficient strategy to expand cancer treatment options. Drug repurposing involves identifying new therapeutic indications for already established drugs that are approved for other indications. Examples include COX inhibitors, beta-blockers, statins, and likewise. In this chapter, some of the candidates for drug repurposing are discussed regarding their pleiotropic effects, existing evidence, advantages, pros, and cons. Specifically, beta-blockers, metformin, statins, losartan, and COX inhibitors were selected due to their widespread clinical use, well-established safety profiles, and prior investigation in cancer patients across various settings. These drugs also converge mechanistically on key hallmarks of cancer, including inflammation, metabolic reprogramming, angiogenesis, and stress- or hormone-related signaling, which collectively influence tumor progression and treatment response. This chapter also focuses on future perspectives, advantages, and limitations of drug repurposing in the era of precision oncology.