Try some melafix (or similar). I've been treating my tank for white spot for 4 days and the fish are really showing stress (clamped fins and flicking), the guy at the LFS recommened melafix to help replace the slime coating the meds had stripped from my fish, in less than 10 minutes almost all fish were acting normal, then they went backwards a bit, after the initial relief is my guess but they are well on the way to normal
katchan