The pharmaceutical science concerned with the gathering, identification, evaluation, monitoring, and prevention of adverse effects with pharmaceutical goods is known as pharmacovigilance (PV, or PhV), sometimes known as drug safety. Thus, adverse drug reactions (ADRs) are a major focus of pharmacovigilance. An ADR is any response to a medicine that is unpleasant and undesired, including ineffectiveness. The stipulation that such a definition only applies to the dosages ordinarily used for the prevention, diagnosis, or treatment of illness, or the alteration of physiological disorder function, was eliminated with the latest change to the relevant law. Medication errors such as overdosing, misusing, or abusing a medication, or being exposed to a drug while pregnant or nursing are also of interest, even in the absence of an adverse event, since they may lead to adverse drug reactions. An Introduction to Pharmacovigilance book relies heavily on the information gathered from patients and healthcare professionals via pharmacovigilance agreements and other sources including the medical literature. Adverse event data obtained by the licence holder, often a pharmaceutical company, must be reported to the local drug regulatory authorities to sell or test the pharmaceutical product in most countries. Ultimately, pharmacovigilance focuses on recognizingrisks connected with pharmaceutical goods and reducing the risk of adverse events occurring in patients. To determine whether or not they are following all applicable laws, regulations, and guidelines throughout the globe, businesses should undertake a thorough audit of medication safety and pharmacovigilance practices.