20th July 2023

A 71-year-old man is living with dementia with Lewy bodies. Over recent months he has become increasingly agitated

A 71-year-old man is living with dementia with Lewy bodies. Over recent months he has become increasingly agitated, with concern that he may be a risk to his own safety. He was started on risperidone three weeks ago. He currently lives in a nursing home and mobilises with one walking stick. He also has a history of diabetes mellitus, angina, and chronic obstructive pulmonary disease.

The nursing home staff are concerned that over the last week, his mobility has declined. He now shuffles, seems stiffer and has got a worsening tremor in his right hand.

What is the most likely cause of the deterioration of his motor symptoms?

Select the SINGLE most appropriate option from the list below. Select ONE option only.