Got a high tolerance
Doing all these drugs is going to build your tolerance to medication in general but young kids (and grown-ass adults even) do it anyway “when [their] age don’t exist” and they act whatever age they want to.
This is specifically a critique to the young people, meaning that they do whatever they want (related to drugs) without caring about the consequences, since they won’t be facing big legal charges while they’re minors.
Also, this line could be referring to those children that get ADHD medication early; they develops a high tolerance to chemicals (drugs, etc.)
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