In this book, we delve into a thorough study of prescriptions and medication consumption profiles in this very vulnerable and important population. The health of the elderly is a complex and challenging issue, especially when it comes to managing multiple health conditions. They often require ongoing pharmacological treatments and may use multiple medications at the same time. Drug interactions pose a significant challenge in contemporary clinical practice. With the frequent use of multiple medications by patients, the chances of interactions occurring that may affect efficacy, safety, and therapeutic outcome increase. These interactions can occur in a variety of ways, involving changes in drug absorption, metabolism, distribution, or elimination. In addition, individual patient characteristics, such as age, health conditions, and concomitant medication use, can influence the potential for drug interactions.