What medicene should i take to prevent runny nose & sneezing?

Try Clariton. It's non-drowsy and works great. I get allergies every once in a while and take Clariton. It really helps. You can also take Zyrtec, but that's really expensive. Never use Benadryl, unless you are trying to sleep, cause it will knock you out. I've never tried Allegra, So I would go with Clariton.