"Interesting Drug" was the fourth solo single released by Morrissey. The song was not featured on one of Morrissey's main studio albums, but can be found on the compilation album Bona Drag along with the B-side "Such a Little Thing Makes Such a Big Difference". It features Kirsty MacColl on backing vocals as well as his former colleagues in The Smiths, Andy Rourke, Mike Joyce and Craig Gannon. All three also appear on the B-side. The artwork for the single features Morrissey photographed by Lawrence Watson. It reached number 9 in the UK, becoming Morrissey's last Top 10 single until 1994.
Edwin Pouncey in NME gave a somewhat mixed review, saying the song was a "finely crafted pop single", but also asked "just what [do] Morrissey's minions see in the man?" Ned Raggett of Allmusic called the song "a vicious slam on the long-loathed by him Tory government and a sometimes slightly too breathless musical and singing rush."