There is a difference between Alzheimer's disease and Dementia.
Dementia is more severe. The person is in or out of memory experiences and becomes agitated and violent. There is a more extreme occurrence of
"Sundowning," where they are agitated and anxious during sunset.
The medications are different, too. Alzheimer's is a more milder short term forgetting. Medication is Aricept. BUT, Dementia would be Excellon, it is not a dopamine deficiency but Acetacolyine deficiency.
If you have the money, get a SPECT or PET scan. The neurologists have the areas deficient in the brain that correspond to the specific type of medication needed.
And a note of extreme caution: most doctors will medicate patients in hospitals and the drugs to curb their agitation could kill them. Heart patients will find the dementia especially painful, because the heart problems invalidate most medications that curb agitation and depression.
I am a health care professional dealing with memory-impaired and head trauma patients for over 20 years.
Music and a determined daily regimine seem to calm the agitation. My last client was an ex-police chief from Boston area. In his latter stages he not only saw "dwarf like people " in the room, voices were whispering to him.
His rage attacks were worse. When he was hospitalized, they put him in a psychiatric ward with no monitors. He fell and broke his hip. His agitation was increased by the reactions to the anesthesia during the operation. They physically restrained him in the hospital because of his reactions and lack of memory as to where he was. It was awful.
Staff in most hospitals and facilities are not prepared for dementia. They will write "refused" for a patients' denial of food, water and pills. You have to have sitters in the hospital with them 24/7.