also a nasal flush and wipe with saline solution helps a lot. I get the headache baaad from chemically scented things and also strong household cleaner stuff (eg carpet shampoo, oven cleaner etc)
I find if I keep a hankie (I use a paper towel) soaked in saline and keep wiping my nose it helps it go away faster too.
avoidance is best with MCS wherever possible, but its hard in this modern chemical world
hearing that re another use for the epsom salts was a great tip too FinLady

thanks!