[at-w]

There is at least some evidence that levoamphetamine is more effective than dextroamphetamine for "hyperactivity and aggressiveness" associated with ADHD (https://jamanetwork.com/journals/jamapsychiatry/article-abst...), and other studies that have found that it has less of certain side effects than dextroamphetamine (though more of others).

A more cynical explanation is that where levoamphetamine and dextroamphetamine alone were not patentable, a new combination of the two (as Adderall is) was patentable, making it more profitable to research.

ADHD is a collection of symptoms that differ enough across individuals that it's almost certain some patients genuinely do respond better to different combinations of drugs.

[mtlmtlmtlmtl]

Interesting research, thank you. Though worth pointing out this study is comparing pure l-amph with pure d-amph. I'm not aware of enantiomerically pure l-amph being used clinically, which is an interesting side note: why not?

Are you aware of studies comparing adderall specifically to d-amph? This has certainly piqued my curiosity.

[salawat]

This actually tracks in my experience. I did Vyvanse for a while but had markedly higher issues with aggression and agitation.

Switched back to Adderall and returned to having near zero issues in terms of problematic aggression. Sample size 1 in my case.