Although medicines are a blessing for patients who are in dire need of treatment, no medicine is 100% safe for every patient at all times. We learn about many of the benefits and harms of a medicine during clinical trials. These studies involve only a few hundred or thousands of carefully selected people, who probably cannot represent the entire group of patients who will eventually use the drug. Furthermore, different people react differently to medicines, because everyone has different risk factors due to genetic variations, other diseases and medications, allergies, social conditions, psychology, and so on. In every treatment decision, the prescriber and patient must decide whether the benefits of the drugs outweigh the possibility of discomfort or harm associated with them. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay These minor or major harms may already be known and recorded on the patient information leaflet or may be completely unexpected at times. Reporting unexpected effects is particularly important to create a complete picture of a drug's safety profile. The more we know about what patients have experienced after using drugs, the more accurately we are informed and any harm can be prevented in the future. Precisely this idea gave rise to the concept of pharmacovigilance. Pharmacovigilance (or vigilant monitoring of pharmaceutical products) includes the science and activities related to the observation, evaluation, understanding, management and prevention of adverse effects of drugs and medicinal devices for use in individuals and populations. It was conceptualized and established in 1968 (Source: The origins of The WHO Program and UMC) by the World Health Organization (WHO) in response to the thalidomide disaster detected in 1961. Together with the WHO Collaborating Center for International Monitoring of Medicines, Uppsala, WHO promotes PV at the national level to improve patient care and safety in relation to the use of medicines by providing reliable and balanced information for the effective evaluation of the risk-benefit profile of medicines and related products. Currently, more than 150 countries are members of the WHO Program for International Drug Monitoring (130 full member countries and 26 associate member countries) [source: Uppsala Monitoring Center WHO Program Members].