Harms are the unwanted, harmful eects of an intervention that are causally related to its use. ey broadly fall into two types:5
■ Type A harms are those that can be anticipated from the known biological eects of an intervention. In the case of a pharmaceutical product, this would include excessive bleeding with an anticoagulant, and hypoglycaemia with an antidiabetic agent. e type A harms with pharmaceuticals are generally dose-dependent within the usual therapeutic dose range.