What Causes Restlessness In The Vascular Dementia Patient?

After greeting
This is a case in my home, a 73 years old man has vascular dementia 2 years ago, he starts his medications with Aricept, Ebixa, Plavix and Zyprexa but in the last 3 months some side effects starts like abnormal gait especially in morning, when he take as seat he changes his positions every 2 seconds (restlessness), when he rest on bed he changes his legs position also every 2 seconds and his left leg toes except the big one shake (upward and downward) involuntary continuously.
whats wrong in this medications and whats your advice?
Many thanks