Methylphenidate cuts my anxiety, but I was dx'd with ADHD (technically it's not a separate diagnosis, b/c the symptoms are all explained by the ASD) so the anxiety is a pretty normal response to the way life feels.
Sertraline might brighten his mood, but its effectiveness as anti-anxiety is hit-or-miss.
The brand name version (Zoloft) worked really well for me (depression-wise) about ten years ago, so a few weeks ago I decided to try it again. Unfortunately I got the generic version and my reaction was HORRID anxiety, panic attacks.
Can you get your son sessions to learn self-hypnosis (it's not magical or esoteric, just deep relaxation)? He could probably learn it w/in a few sessions, but would have to practice it, so periodic follow-ups would be a good support. When I practice those techniques regularly, I can put myself into a really mellow state.
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- NYGOI
NB: contents of above post represent my opinion at time of post only. YMMV, NAYY, and most importantly, IALBTC!