From the very beginning of modern pharmacotherapy there has been the challenge of identifying drug-induced unintended effects as soon and as comprehensive as possible. Any suspicions of an expected or a new problem with a medicine should be well reported, signalled and evaluated. Despite extensive testing of medicines before they are approved for marketing, unexpected and/or rare adverse drug reactions may occur when the medicine is used in normal daily practice. Moreover, also in case that a possible drug-induced problem is already known from the pharmacology of the medicine, e.g. so-called type A effects, it is important to quantify this risk (e.g. in terms of absolute risk, number needed to harm and risk factors), and to put into context when the product is extensively used in clinical practice. This context may include possible strategies for risk manage ment, tailoring the treatment scenario to the individual patient in terms of choice of the medicine, dose and duration, genotyping, consideration of alternative treatments, and so on. Pre-marketing findings regarding safety of medicines are commonly based on the experience of only a few hundreds to thousand people at a maximum, who have been treated in controlled randomised trials. These trials have important limitations in terms of that they [a] usually include rather homogeneous populations (no elderly patients with other diseases, no impaired renal or liver function, etc), [b] they are too small to detect very rare events, [c] they are usual too short to detect long-term effects, [d] they are unable to predict the real world of clinical practice.
KeywordsMedicinal Product Nephrogenic Systemic Fibrosis Gadolinium Base Contrast Agent Acute Interstitial Nephritis Spontaneous Reporting System
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