M.R.
Go to a nuerologist who treats tourette syndrome and other (involuntary) tick disorders. They can help you, and you should be speaking to other adults who have been sucessfully treated for this issue and hear how they feel about their treatment, drug and otherwise, before you prejudege what it is that you want for your son. Your son may be very angry with you as an adult if you do not give him a therapy that would have helped him as a child and let him suffer needlessly because of how you would feel about that stygma of having treated a biolgically based nuerological brain disorder.
This is one of those disorders where if you were to replace "tick" with "pee" you would never, never deny him good medical care to help him be less embarassed or anxious about how his body behaves. While we can control pee, sometimes pee is out of our control, just as the ticks are beyond your son's control. Get him to a nuerologist, and seek out a support group for people who have this issue, have lived with it, and know how controlable this is, or isn't.
People with ticks can be very succesful, very friendly, very smart and very happy people. Ticks, and the conditions that cause them, are not charachter defects, so forget about stygma and get him help.
M.