Then she look at me
She got ADHD
This girl he met has “ADHD” in other words she messed up on alcohol, marijuana etc. Lamar more likely means that she looks at him and says that her AD-HD is her excuse to take Adderall (Which is a prescription pill used to treat ADHD). This line better relates to the theme of the song overall, because it comments on how she uses addy as an excuse for everything.
A lot of kids from the “Section 80” generation have been diagnosed with ADHD (attention deficit-hyperactivaty disorder) since childhood; they are the first people to grow up with medicated stimulants (first Ritalin and then Adderall). The girl justifies her Adderall-snorting on her ADHD. It’s also possibly worth mentioning that AD-HD is pronounced this way so to be used as a triple entendre:
AD-HD — Attention Deficit Hyperactivity Disorder
80-HD — Many people believe cocaine use in the 80s led to high prevalence of ADHD
80-HD — Being from Section 80 (Housing Projects) is a condition in itself that requires medication.
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