Son has Tourette syndrome

My son has Tourettes syndrome since age 5 he was diagnosed. He is 16 almost 17 now.He does take Orap for it but I noticed he is getting more diffrent symptoms(tics). Now he's got Obsessive compulsive Disorder, and several new tics. He refuses therepy, only 2 times he has tried it but he sees it as therepist trying to "brainwash" him.
so my questions are
1- what can I do to try to get my son in counceling (I go and Ive explained to him its not a bad thing)
2- any other parents with teens out there with tourettes?