There could be such a drug connection as you suggest in a song like Desolation Row, but it seems mainly to me to be a comment on what he saw as a decadent and decaying society around him, a theme that Dylan has been writing about for his entire adult life in one way or another. And it's also a comment about various mind games people play...both on themselves and on others...various forms of pretense and hiding from life, such as the marvelous verse about Ophelia:

Now Ophelia 'neath the window
For her I feel so afraid
On her 22nd birthday
She already is an old maid
To her, death is quite romantic
She wears an iron vest
Her profession's her religion
Her sin is her lifelessness
And though her eyes are fixed upon
Noah's great rainbow
She spends her time peaking into Desolation Row

That is simply marvelous poetry. And haven't we all known some people like Ophelia, whose profession is their religion and whose sin (their primary problem) is their lifelessness? Some of us may be people a lot like Ophelia.

Elsewhere on the liner notes he says that "lifelessness is the great enemy". And that's no accident. The same thought is echoed in the verse about Ophelia.

It isn't meaningless writing, it's writing so absolutely full of meaning that it practically jumps off the page.