IQ is bullshit. I've seen people who have high IQ's, and their brains are the same size. So they say that their brains are configured better, or whatever. They have more fatty tissue lining their neurons. But if that's the case, why wouldn't everyone's brain have evolved to use his or her neurons in this way? You'd expect such a trait, one that increases intelligence while reducing the need for metabolic energy, to have reached fixation in the human population. The "better configured brain" argument just doesn't make biological sense. Add in the fact that the brain has incredible plasticity -- so for example one's experience with mathematics can cause his brain to change its configuration in order to perform better on math-related tasks -- and it quickly becomes obvious that IQ is bunk.
IQ is a very accurate and unbiased measurement of social class and cultural privilege. In so far as it is this thing, LSD does not affect it. LSD, on the other hand, does give someone the perspective to notice that my argument is true and that the alternative is self-deceptive, egotistical, hypocritical, insecure human bullshit.
I'm not saying that genes have no effect or that some people don't have broken brains, but if you want a higher IQ score, study for the IQ test.