Summary•Proponents of intravenous filters claim that they remove bacterial contaminants, particulate matter, air emboli and reduce the incidence of phlebitis.•From unstructured observation by the author at a large general hospital not using filters it was concluded that the incidence of complications was no greater than at a hospital having a policy for using these filters. Despite the introduction of a filter that claims to retain endotoxin for up to 96 h, filters are still misused, over used or unused in different departments of the same hospital.•This paper examines the literature that supports and criticizes the advantages and disadvantages of using such filters. The research is reviewed to ascertain whether the widespread use of filters is justified and whether they effectively reduce or prevent the complications of intravenous therapy. The paper reviews the causes and incidence of complications of intravenous therapy and alternative methods used for reducing these complications. The evidence shows conflicting results and argues that complications are inevitable despite the use of filters or careful medical action.•The manufacturer's claims are supported by a plethora of literature but discrepancies are evident and the author remains unconvinced of their widespread use in today's fragile economic climate when the cost of treating the adverse effects of intravenous therapy is con