Adverse drug reactions

An adverse drug reaction is any undesirable effect of a drug beyond its anticipated therapeutic effects occurring during clinical use. In contrast, an adverse drug event is an untoward occurrence after exposure to a drug that is not necessarily caused by the drug.1 When a drug is marketed little is known about its safety in clinical use because only about 1500 patients are likely to have been exposed to it.1,2 Thus drug safety assessment should be considered an integral part of everyday clinical practice since detection and diagnosis often depend on clinical acumen. In this article we review the current status of adverse drug reactions, briefly describing the complexity of the more bizarre reactions and outlining a strategy to eliminate serious adverse drug reactions. Summary points Adverse drug reactions are a common clinical problem They are diagnosed on clinical grounds from the temporal relation between the start and finish of drug treatment and the onset and offset of the reaction Pharmacological adverse reactions are generally dose-dependent, related to the pharmacokinetic properties of the drug, and resolve when the dose is reduced Idiosyncratic adverse reactions are not related to the known pharmacology of the drug, do not show any simple dose-response relation, and resolve only when treatment is discontinued Vigilance by clinicians in detecting, diagnosing, and reporting adverse reactions is important for continued drug safety monitoring