My son got a tic with his first attempt at using a stimulant for adhd. he is now on intuniv, but not working too well. would strattera (atomoxetine) work better?

Maybe. Tics may be : unmasked by one stimulant, but not the the other. Guanfacine, active ingredient of Intuniv, treats tics. If your son's ADHD symptoms need to be reduced in a few days, not a few weeks, his MD can add low dose amphetamine if s/he tried methylphenidate, or vice-versa, then titrate it weekly in small increments. If s/he does so, Intuniv dose should stay the same during stimulant titration.