My father has severe dementia and he either sleeps or is up fidgeting for hours on end. On some days when my father is sleeping during the day, his caregiver is reluctant to change him or to feed him because he will become belligerent when his is awakened. On other days, he is fine. But the belligerent days are becoming more frequent. He is on Atavan. Today for example he was kicking and punching as I and the caregiver tried to change his depends and put on clean clothes. He is very strong and he managed to punch me in the face. He looks so frail but he is very strong for a 95-year-old man.
And I agree about talking to the doctor. If your dad is still trying to punch people while he's on Ativan his dosage may need to be adjusted.