The upper class glass is not filled up with the coughing proof
You are unlikely to find the 1% sipping on syrup.
Although if they are in America, there’s a definite possibility they are abusing prescription medication. Just because it’s produced legally by a pharmaceutical company doesn’t mean it’s good for your health.
Note also that “coughing proof” sounds like “coffin roof” — Lupe is reminding the 1%‘ers that they are not immortal.
To help improve the meaning of these lyrics, visit "Peace of Paper/Cup of Jayzus" by Lupe Fiasco Lyrics and leave a comment on the lyrics box