Antibiotic use in Alzheimer's patients.

My mom is not on hospice care. She is in her 6th year of progressive dementia.

I'm sorry to hear that both of your parents are dying!
Are they on hospice care? Generally, for someone who is terminal, the only medications given are for comfort. I can't imagine why anyone would give a dying person a vaccination. Sometimes, antibiotics may be given, say for strep, because of the pain. You'll need to talk to a medical person about this. If you aren't sure about the primary doctor, get another opinion.