This article presents a list of potentially delirogenic properties of drugs that are currently of relevance to drug therapy in Europe, which was created through a Delphi process including experts from professions relevant to diagnosis and treatment of delirium. The Diagnostic and Statistical Manual of Mental Disorders 5 (DSM 5) defines delirium as a disturbance in attention, awareness and cognition that develops over a short period of time and fluctuates. Possible causes of delirium are manifold: usually delirium is considered to develop in a multifactorial way, caused by inalterable parameters, such as advanced age and pre-existing cognitive impairment and precipitated by modifiable parameters, such as the use of certain drugs or substance withdrawal. Delirium is a serious condition with a pronounced impact on morbidity, mortality and costs to the healthcare system. Circumstances and drugs that might precipitate or worsen delirium should therefore be avoided whenever possible. A list of drugs that might have a detrimental influence on the emergence and duration of delirium has been created using the terms “delirogenity” and “delirogenic” to describe the potential of a drug or withdrawal to cause or worsen delirium. The results are novel and noteworthy, as their focus is on substances relevant to European pharmacotherapy. Furthermore, they represent a methodical consensus from a group of experts of a wide variety of professions relevant to the prevention, diagnosis and treatment of delirium, such as nursing, pharmacy, pharmacology, surgical and internal medicine, neurology, psychiatry, intensive care and medicine, with working, teaching and scientific experience in several European countries practicing both in primary and secondary care.@en