> On the toxicity side, do you have any studies to cite? I wasn’t aware of toxicity, but it’s plausible.

A typical therapeutic dose of amphetamines is around 20mg, topping at around 60mg for serious narcolepsy. Recreational doses can go up to around 1000mg for long-term users with 360mg as the median: https://pubmed.ncbi.nlm.nih.gov/40385390/

That's the area of crazy toxic side effects just from vasoconstriction. Never mind direct effects on the brain.