It's kinda weird that Robotussin added that in , as it is on the cover of his album. Maybe one of the artists snuck it in? xD
I think Robotussin will get a lot of media coverage from that though. It's quite widely known that rappers used to use Ativis cough syrup or Robotussin to make lean. Robotussin is much easier to get as ativis stopped selling their product because it was getting a lot of bad attention in the media.