Yes, they can help, if used occasionally. Lorazepam is addictive, so you have to be careful. There are other drugs, anti-psychotics, which can be used. The major point in all medications is to monitor them carefully.
My mother was violent, aggressive and agitated for a long time. She was on anti-psychotics for years. We gradually weaned her off them once the disease had progressed so far that she was no longer agitated.