If you're into that, there is also a nasal spray version. You can google up Stan Kurtz to find a website on supposed treatment.
I'm warning you, the person is not a doctor and he makes sure to put that disclaimer on his site. I'm also concerned about the "cure all" approach and claims on the site. (Claims to resolve everything from ADHD and autism to even getting rid of alcohol cravings.) If it does help, good, but to me it seems more faith based than actual science. I found it disheartening when I wanted to find some real scientific evidence on the B12 shots and nose spray, I came up dry... The only results I got were from TACA, DAN!, and perhaps an assortment of parents who claimed it worked, which of course posted their testimonials on said websites. It's a bit too sketchy for me to believe it, but if my insurance actually covered it, I may be open to trying just to see what the heck... and see if I gain or lose any abilities and if I lose abilities if it is worth it...
There could also be the placebo effect... That's why I'd like to see an actual scientific study done by an outside and unbiased research group.
If you're open into diving into the unknown, let me know how it goes and in detail. I'm really curious. Call me a scientist, lol.
Sorry I've got no idea, but I wanted to ask your how your son is about receiving injections?
My son is hypersensitive to touch and we have made all kinds of arrangements eg. he will have to have gas if he needs any work on his teeth etc rather than an injection. And I am concerned about if he ever needs to have a blood sample taken etc.