Challenging behaviour is a catch-all term that, in the context of dementia, includes one or combinations of shouting, wandering, biting, throwing objects, repetitive talking, destroying personal possessions and other objects, agitation and general anger, physical attacks on others, and waking others at night. In short, this term describes any behaviour by patients that is deemed to be dangerous to themselves, their fellow patients, and staff, or is considered antisocial within environments where those patients have to coexist with others on a long term basis.

The treatment of such behaviours has traditionally been led by institutional policies of control and containment, consisting of combinations of environmental, mechanical, or chemical restraint.1 However, such approaches are increasingly being challenged both on ethical grounds and for their evidence base. Now a randomised controlled trial in this …