Adverse drug events are unintended and harmful reactions to medications, occurring either at normal dosages or due to medication errors. Adverse drug events encompass allergic reactions, side effects, overdoses, and interactions with other medications, foods, or alcohol. Adverse drug events can vary in severity from mild discomfort to life-threatening conditions. They are a significant concern in healthcare, contributing to hospital admissions, prolonged hospital stays, and increased healthcare costs. Adverse drug events are particularly prevalent among the elderly, who often take multiple medications, increasing the risk of interactions and side effects. Monitoring and managing these events is crucial for patient safety and effective healthcare delivery, often involving careful medication selection, dosage adjustments, patient education, and regular follow-up. Pharmacovigilance, the science of detecting, assessing, understanding, and preventing adverse effects, plays a critical role in minimizing the risk of adverse drug events.