Undiagnosed central anticholinergic syndrome may lead to dangerous complications.

This report describes two cases of central anticholinergic syndrome, the first after general anaesthesia and the other during a prolonged stay in the intensive care unit. The symptoms in both patients resolved soon after physostigmine administration. There was a delay in the diagnosis of central anticholinergic syndrome, which resulted in acute lung injury and unanticipated intensive care unit admission. It is suggested that in cases of abnormal mental recovery after anaesthesia or sedation, the diagnosis of central anticholinergic syndrome should be considered.