IQ tests are biased & not applicable for general usage anyway. Quite possibly, each and every person is similarly intelligent, only adapted to different environments. See some mouse trials from a while back, I'd dig up a link if I had the time.

Many standard "Big Pharma" drugs are also neurotoxic. It's kinda hard finding data on that. Yeah, I know this is not a conspiracy, this is just how the market works etc. Marketing trumps safety.