药物种类繁多,用药途径不同,病人体质各异,因此药物不良反应发生的原因也就极其复杂。本文从药物、机体、给药途径等方面分析药物不良反应发生的原因。1.药物方面的原因1.1药物的药理作用很多药物在应用一段时间后,由于其药理作用,可导致一些不良反应,例如:长期使用皮质激素能 A wide range of drugs, different routes of administration, patients with different physique, so the adverse drug reaction causes are extremely complex. This article from the drug, body, route of administration and other aspects of the analysis of the causes of adverse drug reactions. 1. The reasons for the drug 1.1 The pharmacological effects of drugs Many drugs in the application of a period of time, due to its pharmacological effects, can lead to some adverse reactions, such as: long-term use of corticosteroids