Our psychologist claims that the correct medication in the correct dosage will not change you, but correct you. Recently there have been research studies on SSRI's (and Zoloft is one of these) which has shown that children who do not take medication and suffer from severe anxiety actually lose "brain cells"; while those children taking the SSRI did not lose any brain cells. But, this research is very new and as far as I know, it has not been proven to be "fact". So, not taking a medication may also have consequences.
I guess the question should be one Dr. Phil asks - "and how are things working for you now?'. I do belong to a support group for parents and teachers of children suffering from anxiety and many of our children are taking SSRI's - Prozac, Zoloft, Celexa, etc. some as young as three years of age. Our child has been taking a SSRI for about six years (she is now 12 years old) and we hope she will be able to function without her medication very soon. By the way, SSRI's are not habit-forming and if the medication does not work, then wean your son from it following the doctor's instructions. For us, her medication has been a life-saver.
The best advice that I can give you is when you do start medications, go low and go slow. That means to use a very low dosage to start and not to increase the amount very much or very often (at least several weeks on a dosage before changing). And, if the medication is not suitable (it took three tries before we found the "correct" SSRI for our child), then please be willing to try another med as each body tends to react differently to the various SSRI's. Our child had minor side-effects with each one of the three medications, but the third one seems to work extremely well.
There seems to be a lot of knowledge on the "anxiety" forum on this site re medications; you might want to post your question there and see what additional responses you receive. I wish you the best ...
I wouldn't dare speak for or against medication as I know little or nothing about it, especially in pediatrics, and area where one has got to be absolutely careful.
What I will say though is 'tough love' kick your Son out of the house, even if you have to go out with him. Give him a sense of responsibility by asking him to help with the dishes, polish the windowcill, take the rubbish out.. whatever, but give him little regular jobs. If he's over-weight DO NOT let him sit around the house, don't let him play video games and watch T.V for hours on end, and encourage him to use his imagination. If Children are left to play together and use their imagination, as in playing games, they laugh more, and laughter is a great medicine. Encourage him to eat healthily. Whenever he does good, praise him and reward him for the good he does, and don't put him down for his mistakes. This will take years, but you have start somewhere, and gradually, you'll see improvements here and there. It's never too late, but the later the harder it is.