I'd be a bit dubious about giving anything to a 3 year old, to be honest. As with all medicine almost no studies are conducted with children so the only option is to pro rata adult dosage.
If pushed I guess I'd pick Piracetam, given its virtually flawless safety profile. Just been reading some posts about parents using Piracetam to treat their 6 month old children with Downs Syndrome.
http://www.downsyn.c...75365#post75365http://www.fragilex....html/future.htmhttp://www.fragilex....ylcarnitine.htmAmpakines look like something worth keeping an eye on (at least in the absence of gene or FRMP therapy).
That's my £0.02 but this really calls for someone who knows what they're talking about (LifeMirage, Scott and others).