Can taking vyvanse (lisdexamfetamine) only when needed at a low does cause brain damage? i read a lot of places that it can. is strattera a better choice?

Doubtful: For awhile it was touted that only meth-amphetamine was neurotoxic over time and in some individuals. The problem is that most methamphetamine addicts are using mixtures of psychoactive drugs adulterated with all kinds of junk! the other thing to consider is the outcome studies on "crack babies"- those whose mothers used while pregnant: there seemed to be little evidence for long-term damage.