I get itchy throat too, especially around allergy season and early winters. Halls seem to help, and since it's not too expensive, I just buy the 80 to 100 count bags. The only problem is that it causes me to produce mucus so I have to clear my throat more often when I use halls.
I usually rub my throat and tongue against each other. I'm not sure how to explain it, but I just do it... That relieves the itchiness, but that causes some slight pain. Once I do that, I take a sucret, which helps with the pain. Chloroseptics doesn't help me.
I also use a technique where it's kinda like gargling, but without the water. It's loud... Again, not sure how to explain it, but I just do it. It helps a little bit too.
During allergy season I try not to go outside too much. That helps with the sore/itchy throat. Hope this helps!