Until recently, traditional teaching has been to discontinue MAOI therapy two to three weeks before surgery. The literature and texts relating to the concurrent use of MAOI’s with anaesthesia are confusing, outdated and often contradictory. Significant adverse drug reactions can and have occurred in a minority of patients receiving MAOI’s. The true incidence of such reactions is unknown. While there are several recent clinical reports indicating the safety of these agents in combination with anaesthesia, only small numbers of patients are described in each series. Until it is possible to define those individual patients in whom adverse reactions are likely to occur, all patients must be assumed to be at some level of potential risk.