Is there medication to help with Alzheimer's agitation?

There a lot of medications for agitation but, the problem is you don't really know which one help the person in need. My opinion do not play doctor at home. It is very important to have that person evaluated by a specialist in the hospital setting so, they can administered the medication and be able to observe the side effects and change the dosage, use different ones, etc.
An another hand the agitation may be due to UTI, pneumonia, other infections, side effects of other medications, sundown syndrom, anxiety, demanding attention,etc.