Alzheimer’s causes changes in behaviour that many people find most distressing. The progressive deterioration of brain cells is the main cause of behavioural symptoms. In the early stages, these can be irritability, anxiety and depression; in later stages, anger and agitation, aggression, restlessness, pacing, physical or verbal outbursts, delusions, sleep disturbances and hallucinations. It is important to get supports in place while the disease is in the earlier stages. A medical evaluation can determine if changes in behaviour are due to other factors such as drug side effects, discomfort from infections and other conditions.