Pharmaceutical pollution, a growing global concern, impacts our environment in ways often overlooked. While plastic and air pollution dominate discussions, chemical substances from medications—such as painkillers, antibiotics, hormones, and antidepressants—are increasingly contaminating water sources. These pharmaceuticals enter ecosystems through human and industrial waste, creating toxic conditions for aquatic life. Even in low concentrations, they can disrupt biological processes, alter reproductive systems, and hinder essential functions like photosynthesis. This chapter explores the harmful effects of various drugs, including painkillers, beta-blockers, antibiotics, endocrine disruptors, anticancer drugs, and more. As we face rising pollution, understanding these invisible threats is vital for safeguarding our health and the planet’s delicate ecosystems.